劳动力供大于求的突出矛盾与技能人才相对不足的结构性矛盾并存，较低的人力资本存量已经成为民工外出务工就业的重要障碍。基于此，提出本文的研究问题：外出民工人力资本增长的途径及机制。以往研究农民工人力资本增长多从流出地或者流入地角度出发或者局限于一个区域，研究其人力资本对于收入或者就业的影响,并没有系统分析外出民工人力资本增长途径及保障机制。本文以河北省清苑县外出民工为例，从流出地和流入地两个角度出发，分析个体、企业以及区域三要素对民工人力资本增长的影响，并提出相应的对策建议，以期为加快农民工人力资本的增长、促进其收入的增加、实现农村劳动力顺利转移提供新的视角。主要采用的研究方法包括问卷调查法、文献研究方法、实证研究方法、案例分析方法。通过随机抽样和分层抽样方法，在清苑县18个乡镇32个自然村进行问卷调研，获得225份有效结构化问卷，并对个案进行深入访谈，获取一手数据，运用定性和定量相结合的分析方法，首先了解人力资本现状，分析其增长途径，并深入到不同的工种、不同的打工地剖析其人力资本增长的差异，并提出相应的对策建议。本研究得出以下结论：（1）不同的个体、企业、区域对于其人力资本（文化程度、培训情况、证书情况）存在显著的差异。（2）从总体来看，外出民工人力资本增长的主要方式是非正式学习（跟其他同事学习、自己摸索、向同行的老乡请教、拜师学习），其次是单位培训。从个体投资来看，外出民工的长期的职业生涯、劳动力市场竞争程度以及用人单位岗位升迁制度对于其人力资本提升具有重要影响；从企业投资来看，企业性质、企业规模、企业所处的市场竞争程度以及产品的技术含量影响企业对民工的培训次数和培训意愿，企业规模越大、产品技术含量越高的企业越愿意对民工进行培训；从政府投资来看，无论输出地和输入地，对于民工人力资本关注较少，没有针对民工提供相应的设施或制度。个体提升意愿和提升能力、单位培训、区域因素对于民工人力资本提升有重要影响。（3）通过对区域要素与人力资本进行相关分析，发现各要素与人力资本均不具有统计上的显著意义，但这并不表明区域对于民工人力资本增长没有影响。一方面，政府并没有发挥主体作用，没有真正关注民工问题；另一方面民工的城市融入性较差，使得这一作用需要一段时间才能显示出来；第三是由于指标选取存在一定问题。（4）本文选取不同地区、不同行业民工的人力资本进行研究，发现农民工人力资本增长的主要途径仍然是干中学。不同行业民工人力资本增长意愿存在一定差异，最后提出相应的政策建议。

Migrant workers is a special group which appears in the process of Chinese social economic development. Their social identity is “peasant”; but their profession is “worker”. They contribute significantly to the Chinese construction of industrialization and urbanization. However, treated inequitable on some aspects, such as Labor and employment, labor remuneration, health and safety, social security and human dignity, they become social vulnerable groups, which has been pay close attention by society. Migrant workers are in weak position which causes a series of problems are mainly because of the lack of human capital investment and knowledge. If this situation can not be improved efficiently, it will become the important restricted factors which country labor force migrate to city, and will surely restrict the process of Chinese urbanization and economic development. Therefore, the government should increase investment to migrant workers’ human capital. However, the key to solve the problem is to research how to improve the level of migrant workers’ human capital. In the process of migrant workers’ human capital investment, there are three subjects of investments: migrant workers own, employer, and government. Because human capital investment has obvious external characteristic, Enterprises are unwilling to invest because of the consideration on the investment and profit. And migrant workers also do not have the ability to pay the fees of human capital investment because of their low income. Moreover, due to the process of social transformation，the improvement of migrant workers’ human capital involves in all kinds aspects of economy and social life: Optimization and upgrading of industrial structure, the process of urbanization and rural construction, enhancing the quality of labor force, and the stability of the society. Therefore, the government, as the main part in the social management and public service, should clear their responsibility and play a leading role in migrant workers’ human capital investment. In this paper, we analyze the the mechanism of the growth of human capital from the micro level of individual migrant workers to take Qingyuan County as a study, and put forward specific suggestions to speed up the promotion of migrant workers ' human capital and promote the labor transfer smoothly . We use literature research method, Questionnaire survey method, empirical analysis method, case study method. The main conclusions are as follows: 1)There is a significant difference in human capital for different person, enterprise and city; 2)Informal learning takes a large contribution to the growth of human capital; 3)Regional factors affect personal investment and enterprise investment.