党的二十大报告指出，“高质量发展是全面建设社会主义现代化国家的首要任务”。随着大数据、人工智能、云计算和区块链等数字技术的不断进步，数字经济成为推动中国经济高质量发展的新动能。作为生产、分配和流通等经济环节的主要参与者，企业是最重要的市场主体。企业高质量发展是经济高质量发展的微观表现和重要基础。数字化转型是数字技术与企业的生产、运营与管理等方面深度融合的过程，引领了生产力和生产关系的变革。数字化转型不仅优化了传统经济形态，还促进了新产业、新模式和新业态的发展。因此，深入分析数字化转型影响企业高质量发展的理论机制和内在逻辑，对促进数字经济发展和实现高质量发展目标具有极其重要意义。本文聚焦于数字化转型与企业高质量发展之间的关系，主要研究了以下几个核心问题：第一，数字化转型如何影响企业高质量发展以及背后的作用机理是什么？第二，数字化转型对企业高质量发展的影响是否存在异质性和门槛效应？第三，智慧城市政策能否促进域内企业高质量发展？该政策的影响机制是什么，并且是否表现出差异化效果？

基于此，本文从理论分析和实证检验两个方面探索了数字化转型对于企业高质量发展的影响。首先，根据数字化转型和高质量发展的相关经典理论，在生产函数中引入企业数字化转型的研发活动，分析数字化转型对企业高质量发展的影响，并对作用机理进行了阐述。第二，从时间变化趋势、行业差异和区域分布三大视角深入探索了数字化转型和高质量发展的特征。第三，利用2007-2019年3346家中国A股上市公司的非平衡面板数据实证检验了数字化转型对企业高质量发展的影响，进一步从外部宏观环境、内部微观特征和数字化转型细分类别三个方面进行了异质性分析，并基于盈利波动性和现金流状况展开门槛效应讨论。第四，从创新、人力资本、成本、效率和供应链五个维度实证检验了数字化转型影响企业高质量发展的内在传导机制。最后，将智慧城市政策作为数字化转型的准自然实验，基于多期双重差分进一步检验了智慧城市政策对域内企业高质量发展的影响。本文得出的主要结论如下：

（1）在数字经济迅速发展的时代背景下，中国上市公司的数字化转型程度不断加深。在样本期内，数字化转型程度指数由0.1711增长至1.7163，呈现出明显的上升趋势。不同类型的数字技术发展也存在显著差异，企业更加关注将数字技术应用于实际业务中，底层技术如人工智能技术和区块链技术的发展尚有很大的空间。数字化转型不同地区及行业间显示出明显的差异，揭示了一个不容忽视的“数字鸿沟”现象，特别是在中西部地区与东部地区、资源密集型行业与其他行业之间的数字化转型差距显著。胡焕庸线作为一条虚拟的经济地理分界线，在数字化转型的进程中也展现出了显著的分割效应。

（2）数字化转型对企业高质量发展具有显著的激励作用，其效果不仅受到数字基础设施、市场化程度等外部宏观环境的制约，还受到要素密集度、管理层结构等内部微观特征的调节。外部宏观环境异质性显示，完善的数字基础设施和强有力的知识产权保护为企业创造了良好的外部环境，从而保障数字技术有效转化为生产力；数字化与市场化之间存在着互补效应，数字化转型对市场化程度低的地区的企业高质量发展促进作用更为明显；数字化转型所带来的“数字红利”能缩小区域间企业高质量发展的差距，有利于区域经济协调发展。内部微观特征的异质性显示，数字化转型有助于劳动密集型和技术密集型企业的高质量发展，但对资本密集型企业的影响不显著；数字化转型对融资约束低、企业市场价值高、非高污染、非制造业的企业的高质量发展影响更大；在竞争激烈的行业中，数字化转型成为企业保持竞争力的有效途径。两职分离有助于数字化转型的顺利实施并影响生产过程，进而促进企业的高质量发展。此外，从企业数字化转型的细分类别来看，数字技术应用和底层技术都能促进企业的高质量发展，但数字技术应用的促进作用更加显著。

（3）数字化转型对企业高质量发展的影响存在盈利波动性单一门槛效应。当盈利波动性超过门槛值0.0237时，数字化转型无法实现企业高质量发展水平提升效果。此外，良好的现金流状况是保障数字化转型顺利进行的关键因素。数字化转型要想有效地推动企业高质量发展，必须确保现金流状况跨越门槛值0.0665。只有当现金流状况超过这一门槛值时，企业才具备足够的财务资源来支持数字化转型的深入实施，进而推动企业的高质量发展。这一门槛值可以被视为企业在数字化转型过程中资金调度的最低健康标准。

（4）数字化转型为企业构建了一个全方位高质量发展的新框架，通过创新驱动、人力资本结构优化、成本控制、效率提升以及供应链调整，全面推动企业实现高质量发展的目标。在创新层面，数字化转型激发了企业的创新潜能，为高质量发展奠定了基础。在人力资本层面，数字化转型优化了企业的人才结构，吸引了更多高学历人才，为企业的持续发展提供了强有力的人才支持。在成本和效率层面，引入高效的数字技术使企业流程更加精简高效，显著降低了运营成本，实现了成本节约与效率提升的双重优势，为企业的高质量发展创造了更多空间。在供应链管理方面，数字化转型破除了传统的供应链集中模式，降低了对单一客户的依赖，确保了企业运营的稳定性和可持续性。

（5）智慧城市政策推动了域内企业高质量发展。该政策在不同区域和不同类型的企业中发挥了作用存在差异。外部宏观环境异质性显示，健全的知识产权体系为智慧城市政策的实施提供了一个更为有利的环境，进而有效地促进了企业高质量发展。在市场化程度较低的地区，智慧城市政策填补市场机制的不足，从而更有效地发挥其对企业高质量发展的促进作用。内部微观特征异质性显示，智慧城市政策对域内的非制造业、非高新技术行业、国有企业和两职分离的企业的全高质量发展的促进作用更大。同样的，智慧城市政策通过提升企业创新能力、优化人力资本结构、降低企业成本、提高营运效率和降低供应链集中度，从而提高了企业高质量发展水平。

本文的创新点在于：第一，将数字化转型的研发活动引入生产函数中，进一步从创新、人力资本、成本、效率和供应链五个维度系统地梳理了数字化转型影响企业高质量发展的作用机制。数理建模和理论分析两种方法被有效地结合起来，弥补了当前数字化转型相关理论机制分析的不足，为数字化转型促进企业高质量发展的研究构建了一个完整的、逻辑性强且具有普遍适用性的理论分析框架。第二，从多重视角深入分析了数字化转型对企业高质量发展的影响，是对现有文献的有益补充。在微观企业层面，在识别数字化转型和企业高质量发展的动态演化规律和行业分布特征基础上，验证了数字化转型对企业高质量发展的促进作用，并基于内部微观特征进行了异质性分析。在区域层面，分析了数字化转型和企业高质量发展的区域分布特征，揭示了数字化转型在区域分布存在“数字鸿沟”现象，并从外部宏观环境维度进行了异质性分析，发现了数字化转型的“数字红利”效应，验证了其助力区域经济平衡发展的作用。在城市层面，将智慧城市政策视为数字化转型的准自然实验，从城市层面探究了数字化转型相关政策的宏观效应。第三，在理论分析的基础上，多维度、深层次和全方位对数字化转型促进企业高质量发展的机制路径进行了实证检验，拓展和深化了原有文献的机理分析。对数字化转型的各个分项进行了对比分析，揭示了数字技术应用与底层技术的差异化效应，强调了管理层结构和企业价值等内部微观特征的调节作用，并进一步检验了数字化转型对企业高质量发展影响存在盈利波动性和现金流状况门槛效应。本文的研究为促进新旧动能转换、合理配置资源、推动中国传统产业向中高端产业的转型，以及提升各行业的生产率，从而推动企业和中国经济的高质量发展，提供了理论支持和决策参考。

The report of the 20th National Congress of the Communist Party of China emphasized that "high-quality development (HQD) is the primary task in comprehensively building a modern socialist country." With the continuous advancement of digital technologies such as big data, artificial intelligence, cloud computing, and blockchain, the digital economy has become a new driving force for the HQD of China's economy. As main participants in economic sectors like production, distribution, and circulation, enterprises are the most important market entities. The HQD of enterprises is a microcosm and critical foundation for the economic HQD. Digital transformation (DT) not only optimizes traditional economic forms but also fosters the development of new industries, models, and business formats. Therefore, a deep analysis of the theoretical mechanisms and intrinsic logic of how DT affects the HQD of enterprises is of utmost importance for promoting the development of the digital economy and achieving HQD goals. This thesis focuses on the relationship between DT and HQD of enterprises, addressing several core issues: First, how does DT affect HQD, and what are the underlying mechanisms? Second, does the impact of DT on HQD vary across sectors or regions, and are there any threshold effects? Third, can smart city policies promote HQD within local enterprises, and what are the mechanisms of this policy impact, including any differentiated effects?

Based on this, the thesis explores the impact of DT on enterprise HQD from both theoretical analysis and empirical testing. Initially, it incorporates enterprises' DT R&D activities into the production function model, analyzing the impact on HQD and explaining the underlying mechanisms. It then explores the characteristics of DT and HQD from the perspectives of time trends, industry differences, and regional distribution. Empirically, using unbalanced panel data from 3,346 Chinese A-share listed companies from 2007 to 2019, it tests the impact of DT on HQD, further analyzing heterogeneity from the aspects of external macro environments, internal micro characteristics, and detailed categories of DT, and discusses threshold effects based on profitability volatility and cash flow conditions. Moreover, it empirically tests the intrinsic transmission mechanisms of how DT affects HQD across five dimensions: innovation, human capital, cost, efficiency, and supply chain. Lastly, by considering smart city policies as a quasi-natural experiment, it further tests the impact of these policies on the HQD of local enterprises. The main conclusions are as follows:

(1) In the era of rapid development of the digital economy, the degree of DT of Chinese listed companies has continuously deepened. During the sample period, the DT index increased from 0.1711 to 1.7163, showing a significant upward trend. There are notable differences in the development of various types of digital technologies, with enterprises increasingly focusing on applying digital technologies in their actual business operations, although there is still considerable room for the development of underlying technologies like artificial intelligence and blockchain. DT shows significant regional and industry differences, revealing a notable "digital divide," particularly between central-western and eastern regions, and between resource-intensive and other industries. The Hu Line, a virtual economic-geographical boundary, also shows significant segmentation effects in the process of DT.

(2) DT significantly stimulates the HQD of enterprises, with its effects not only restricted by external macro environments like digital infrastructure and marketization levels but also modulated by internal micro characteristics such as factor intensity and management structure. External macro environment heterogeneity shows that well-developed digital infrastructure and strong intellectual property protection create a favorable external environment for enterprises, thereby ensuring the effective transformation of digital technology into productivity; there is a complementary effect between digitalization and marketization, with DT having a more pronounced impact on the HQD of enterprises in regions with lower degrees of marketization; the "digital dividend" from DT can narrow the gap in HQD between regions, benefiting coordinated regional economic development. Internal micro characteristic heterogeneity indicates that DT aids the HQD of labor-intensive and technology-intensive enterprises, but its impact on capital-intensive enterprises is not significant; DT has a greater impact on the HQD of enterprises with low financing constraints, high market values, non-high pollution, and non-manufacturing industries; in highly competitive industries, DT becomes an effective way for enterprises to maintain competitiveness. The separation of two positions facilitates the smooth implementation of DT and affects the production process, thereby promoting the HQD of enterprises. Additionally, looking at the detailed categories of enterprise DT, both digital technology applications and underlying technologies promote HQD, but the promoting effect of digital technology applications is more significant.

(3) The impact of DT on the HQD of enterprises exhibits a single threshold effect of profitability volatility. When profitability volatility exceeds the threshold value of 0.0237, DT cannot effectively enhance the level of HQD of enterprises. Moreover, a good cash flow condition is a key factor in ensuring the smooth progress of DT. For DT to effectively promote HQD of enterprises, it is essential to ensure that cash flow conditions surpass the threshold value of 0.0665. Only when the cash flow condition exceeds this threshold value do enterprises have sufficient financial resources to support the deep implementation of DT, thereby promoting HQD. This threshold value can be regarded as the minimum healthy standard for financial management during the DT process.

(4) DT has constructed a comprehensive new framework for the HQD of enterprises. It promotes HQD through innovation-driven strategies, optimization of human capital structure, cost control, efficiency enhancement, and supply chain adjustments. On the innovation front, DT stimulates the innovative potential of enterprises, laying the foundation for HQD. In terms of human capital, DT optimizes the talent structure of enterprises, attracting more highly educated talents and providing strong support for sustainable development. In terms of costs and efficiency, the introduction of efficient digital technologies has streamlined business processes, significantly reducing operating costs and achieving the dual benefits of cost savings and efficiency improvements, thus creating more space for HQD. In supply chain management, DT has broken away from traditional centralized supply chain models, reduced dependency on single customers, and ensured the stability and sustainability of business operations.

(5) Smart city policies have promoted the HQD of local enterprises. The policy has had varying effects across different regions and types of enterprises. External macroenvironment heterogeneity shows that a sound intellectual property system provides a more favorable environment for the implementation of smart city policies, thereby effectively promoting HQD of enterprises. In areas with lower marketization levels, smart city policies compensate for the deficiencies of market mechanisms, thus more effectively promoting HQD. Internal micro-characteristic heterogeneity shows that smart city policies have a greater promotional effect on HQD of non-manufacturing, non-high-tech industries, state-owned enterprises, and enterprises with separate managerial positions. Similarly, smart city policies improve enterprise innovation capabilities, optimize human capital structure, reduce enterprise costs, enhance operational efficiency, and decrease supply chain concentration, thereby raising the level of HQD in enterprises.

The innovation of this thesis lies in: First, the introduction of DT research and development activities into the production function, further systematizing the mechanism by which DT impacts the HQD of enterprises across innovation, human capital, cost, efficiency, and supply chain dimensions. Mathematical modeling and theoretical analysis have been effectively combined, filling the gaps in current analyses of DT mechanisms and constructing a complete, logical, and universally applicable theoretical framework for the study of how DT promotes HQD of enterprises. Second, by analyzing the impact of DT on HQD in enterprises from multiple perspectives, this thesis serves as a beneficial supplement to existing literature. At the microenterprise level, after identifying the dynamic evolution and industry distribution characteristics of DT and HQD of enterprises, the thesis verifies the promotional effect of DT on HQD and conducts heterogeneity analysis based on internal micro-characteristics. At the regional level, it analyzes the regional distribution characteristics of DT and enterprise HQD, revealing the "digital divide" phenomenon in regional distribution, and from an external macroenvironment perspective, it analyzes the heterogeneity, discovering the "digital dividend" effect of DT, verifying its role in supporting balanced regional economic development. At the city level, considering smart city policies as a quasi-natural experiment of DT, the thesis explores the macro effects of related policies from the city perspective. Third, based on theoretical analysis, the thesis empirically tests and deepens the mechanism pathways by which DT promotes HQD of enterprises through multi-dimensional, deep, and comprehensive analysis, expanding and deepening the mechanistic analysis of existing literature. The thesis also compares various aspects of DT, reveals the differentiated effects of digital technology applications and underlying technologies, emphasizes the regulatory role of management structures and enterprise value among internal micro-characteristics, and further verifies the existence of profitability volatility and cash flow condition threshold effects in the impact of DT on HQD of enterprises. This research provides theoretical support and decision-making references for promoting the transformation of old and new energies, rational resource allocation, pushing China's traditional industries towards mid-to-high-end industrial transformation, and enhancing the productivity of various industries, thereby promoting the HQD of enterprises and the Chinese economy.