在旧国际规则式微、新国际规则亟待确立的国际背景和经济发展进入“新时代”的国内背景下，我国积极把握机遇、应对挑战，秉承着持续扩大改革和深化开放的决心，坚持发展外向型经济，从2013年开始实施自由贸易试验区战略。随着国家顶层设计的不断优化和地区发展需求的持续升级，我国自由贸易试验区在七年内进行了六次扩容升级，现已初步形成“1+3+7+1+6+3”的总体格局，并取得了一系列可复制、可推广制度创新成果。

作为扩大改革“排头兵”和深化开放的“试验田”，从设立之初，自贸区的发展建设和政策效应就备受关注。基于此，本文以我国前四批次自贸区为研究对象，通过实证方法评估了自贸区设立的贸易效应和投资效应。首先，本文就当前有关自贸区建设和自贸区政策效应评估的文献进行梳理归纳，深入探究了自贸区促进地区贸易和投资增长的内在作用机制。其次，本文对我国自贸区的建设背景、建设历程以及建设现状进行了阐述。再次，使用多期双重差分法，基于2009年至2019年我国274个地级市的面板数据进行实证分析，运用多种拓展方法进行了稳健性检验和内生性检验，分析了不同地区和不同批次自贸区的异质性影响，并深入考虑了排除其他区域性政策后的政策效应。实证结果显示：（1）自贸区的设立能够显著促进地区对外贸易和外商投资的增长。（2）自贸区设立对对外贸易和外商投资的影响具有明显的地区异质性和批次异质性。西部地区自贸区的政策效应要强于中部和东部地区；第一、三批次自贸区的政策效应要强于第二、四批次自贸区。（3）考虑到保税区政策和“一带一路”政策后，自贸区的贸易效应被掩盖了，投资效应依然显著。最后，在上述实证结果的基础上，本文从促进区域协调发展、实施差异化发展战略、持续复制推广先进经验、积极参与国际规则制订四个方面提出了政策建议，以期为我国自贸区的持续性发展提供经验借鉴和理论参考。

In recent years, the old international economic and trade rules are on the decline and new international rules need to be established urgently. Meanwhile, China's economic development has entered a "New Era". Under such international and domestic background, China is grasping opportunities and responding to challenges, adhering to the determination of continuing to expand reform and deepen opening-up, and developing an export-oriented economy. From 2013, China began to implement the strategy of free trade zones. With continuous optimization of national top-level design and continuous upgrading of the needs of regional development, the experimental free trade zones in China have expanded six times in seven years, and have formed the overall pattern of "1+3+7+1+6+3" initially, and has obtained a series of replicable and scalable institutional innovation results.

As a "pilot field" for expanding reform and deepening opening-up, the development, construction and policy effects of the free trade zones have attracted much attention since its inception. Based on this, this paper takes the first four batches of free trade zones as the research object, and evaluates the trade effect and investment effect of free trade zones through the empirical method. First of all, this paper reviews and summarizes the current literature on the construction and the policy effects of free trade zones, and explores the internal mechanism of free trade zones to promote regional trade and investment growth. Secondly, this paper expounds the background, course and present situation of the construction of China's free trade zones. Thirdly, based on the panel data of 274 Chinese prefecture-level cities from 2009 to 2019, this paper uses multi-period difference-in-differences model to conduct empirical analysis. Multiple expansion methods are used to conduct robustness test and endogeneity test. Meanwhile, the heterogeneity of different regions and different batches of free trade zones are analyzed, and the policy effects of excluding other regional policies are deeply considered. The empirical results show that: (1) the establishment of free trade zones can significantly promote the growth of regional foreign trade and foreign direct investment. (2) The impact of the establishment of free trade zones on foreign trade and foreign investment has obvious regional and batch heterogeneity. The policy effect of the free trade zones in the western region is stronger than that in the central and eastern regions. The policy effect of the first and third batch of free trade zones is stronger than that of the second and fourth batch of free trade zones. (3) Considering the bonded areas and the "One Belt, One Road" policy, the trade effect of free trade zones is covered up, but the investment effect is still significant. Finally, on the basis of the above empirical results, this paper puts forward policy suggestions from four aspects: promoting regional coordinated development, implementing differentiated development strategy, copying and promoting advanced experience, and participating in the formulation of international economic and trade rules. It is hoped that these suggestions can provide experience and theoretical reference for the sustainable development of China's free trade zones.