It is of great significance to activate the potential of intermediary service of rural collective in farmland rental markets to optimize the allocation of farmland resources as well as increasing farmers’ income. From the perspective of intermediary service function of rural collective， a theoretical framework was built to analyze the effects of rural collective’s intermediary service on farmland rental market and farmers’ income and propensity score matching method was applied to identify the empirical effects based on 931 farmland rental farmers in 12 provinces. Results showed that： Firstly， the farmland rental quantity reveals the positive effects of application of intermediary service of rural collective on farmland rental scale with obvious asymmetry， in that it only promotes the expansion of farmland rent-in scale. Secondly， the farmland rental quality demonstrates that the application of intermediary service of rural collective has positively prolonged the farmland rental period as well as improve the probability of written contract， namely， the intermediary service by rural collective can effectively guide farmland rental with standardization and longer period. Thirdly， farmers’ income indicates that applying intermediary service of rural collective has effectively boosted farmers’ income， which is more obvious with farmland rent-in farmers. Therefore， in the following process of market-oriented farmland reform， intermediary service of rural collective should be paid enough attention and rural collective should play the role of “mediator” in farmland rental markets so that a win-win situation of farmland rental with efficiency and increasing farmers’ income will be achieved.