Abstract: China has established mortgage insurance system which is composed of suretyship of specialized agency and insurance company,however,there are still many problems.This article fully expounded the general theory of mortgage insurance,analyzed in depth the problems of China's mortgage insurance,put forward that in the construction process of China's mortgage insurance,government should play a leading role,estabilsh policy-oriented mortgage insurance agency to provide low down payment mortgages insurance for the middle-low income residents.In addition,the government may encourage,guide and support the development of commercial mortgage insurance according to the actual needs of the housing market.