Abstract: Introducing social trust into the Free Capital Vertical Linkage model (FCVL), this paper constructs a model of social trust and industrial coagglomeration to study the innermechanism that social trust causes industrial coagglomeration. Theoretical analysis shows that the higher the degree of social trust is, the higher industrial coagglomeration level will be, and the greater economic contribution industrial coagglomeration will make. By pairing 19 kinds of manufacturing industry data in the inputoutput table of 30 provinces and cities in China, the above conclusion is verified though gradually adding control variables and overcoming endogeneity. Considering the differences in development level, this paper does regional heterogeneous study and finds that the marginal effect of social trust on industrial coagglomeration in eastern areas and highermarketization areas is significantly higher than that in middle and west areas and lowermarketization areas. Therefore, raising the level of regional social trust to promote industrial coagglomeration and highquality regional economic growth, especially the eastern areas and highermarketization areas, should be one of the priorities of local government.

Key words:  social trust , industrial coagglomeration , transaction cost

摘要： 本文在自由资本垂直关联的协同集聚模型中引入社会信任要素，通过构建理论模型考察社会信任作用于产业协同集聚的内在机制，研究分析表明社会信任水平越高，产业协同集聚程度也就越高，对经济发展的贡献越大。基于此，本文对我国30个省份投入产出分析表中的19种制造业门类数据进行了两两任意匹对，在逐步增加控制变量和克服内生性后，均能验证上述结论。鉴于发展程度差异，本文又进行了区域异质性研究，发现社会信任对东部地区和高市场化地区的产业协同集聚的边际效应明显高于中西部地区和低市场化地区。因而，通过提升地区社会信任水平促进产业协同集聚，推动区域经济高质量增长，应是地方政府工作的重点之一，特别是东部较发达地区和市场化程度较高的地区。

关键词: 社会信任 , 产业协同集聚 , 交易成本