Abstract: At both the empirical facts and policy design levels, agricultural socialization services have been assigned the function of the green effect; however, the issue of the green development effect of agricultural socialization services has not been systematically studied. Starting from the macro background of agricultural and rural modernization, by constructing an integrative theoretical framework, we try to incorporate the green total factor productivity, the characterizing variables of agricultural socialization services and agricultural green development into a unified analytical framework. With the decomposition terms of agricultural green technical efficiency and agricultural green technical progress as the mediator variables, the functioning mechanism of the green effect of agricultural socialization services was explained. And with the heterogeneous farm household factor endowment as a moderating variable, the circumstances under which it has enhancement impact on agricultural socialization services’ green development effects was explored. The study showed that the direction of the impact of agricultural socialization services on green total factor productivity depended on the elements with the strongest force, and the level of comprehensive factor endowment at the vertical level and the type of factor endowment at the horizontal level of the farmers. There was a certain threshold range of the impact, and the threshold effect of the moderating effect of different types of factor endowment was different. Based on the results, the future research can refine the research perspectives, enrich and expand the path of the effect of agricultural socialization services, and use agricultural big data and continuous survey of large samples to examine the policy effect in depth. This theoretical framework provides a new theoretical reference for re-exploring the modernization path of small-scale agriculture, optimizing the supply of socialized services for farmers, realizing the expansion of agricultural functions, and providing realistic possibilities for the government to reset the starting point of modern agricultural policies.