Abstract: As an innovation of the rural system reform, the reform of stock cooperation system of village collective economy was some kind of arrangement of income distribution system based on identity of the collective members. Difference-in-difference model has been used to do the analysis basing on a case study in Jianggan District Zhejiang Province. It was concluded that the reform of stock cooperation system of village collective economy could increazed the peasants’income during the reform-finish year and the following three years. But the positive effect was not significant since the fourth year. The reason might be the flaw of fair and reasonable interest distribution mechanism. It was recommended that to build a fair and reasonable interest distribution mechanism was of great importance besides the effort to ensure the increase of the public interest amount, and only in this way could we make sure that the peasants’incomes do increase.