Since the 1990s,petty loan(microfinance) was introduced to China for solving the poor population problem of China.After over a decade practice,petty loan is proven to have feasibility in China.In China s agencies for petty loan,however,there is not a single agency to succeed.This paper tries to find the reason for un-success and gives some policies and suggestions in order to promote the development of petty loan in China and to promote socialism village reconstruction and harmonious society construction.