| Pension insurance is not only related to the individual’s vital interest, but also related to the long-term stability in a region, and is closely related to China’s reform,development and stability. China’s pension insurance system was founded in the early days of the republic foundation, and the pension insurance system has experienced many significant changes since 1984.After the reform and exploration in the nearly 30 years of time, China’s pension insurance has formed the framework of multi-level and SP&IPA.In recent years, the sustainability of basic pension insurance system has caused wide public concern. Endowment insurance fund is the material basis for pension insurance system, to realize the financial sustainability of pension insurance is the precondition of pension insurance system. At present, due to ageing population,empty account, low investment income, rough supervision and management, the financial sustainability of the pension system in China is facing the huge challenge.In order to solve these problems and maintain the healthy operation of endowment insurance system, it is necessary to forecast the future revenue and expenditure scale of endowment insurance in a long period. Finally, it puts forward several corresponding countermeasures according to the prediction results.The paper is divided into six parts: the first part introduces the background and significance, research status, methods and main contents. The second part mainly discusses several problems. It introduces the connotation of pension insurance system,related theory and principle of pension insurance system. The third part teases the evolution of China’s pension insurance system, states the present situation and analyses current problems of the endowment insurance in terms of fund-raising,payment, investment and management. The fourth part forecasts the revenue and expenditure gap in future 30 years. On the one hand, it calculates the population size,gender construction and age structure in next 30 years, analyses aging trend in the future; on the other hand, it predicts the possible pension gap in 2040-2015 based ongrey theory. In the fifth part is about policy advice improve the financial sustainability of basic pension insurance system, in order to relieve the pressure of pension insurance fund balance in future China. The sixth part is the conclusion and prospect,which summarizes the main conclusions and deficiencies of the study. |