Abstract: With the intensified process of population aging (ageing population) and the comprehensive covering of the New Rural Social Endowment Insurance, rural elderly population and pension surge in demand increase, and rural pension payments imbalance and unsustainable risk rapidly increase. According to pension financing and payment, rural pension income, expenditure and balance actuarial models with entirety method are constructed, and the rural pension change and trend are predicted by selecting and adjusting key parameters based on the investigation data (effective questionnaire = 5031)of six experimental counties (city or district)in three provinces in east, middle and west China where the New Rural Social Endowment Insurance carried out, and its sustainability with simulation studies are analyzed, and some basic reform ideas are proposed to enhancing the sustainability of rural pension according to the forecasting results in this paper. The results show that the increase of policy parameters such as payment rate and subsidy rate, economic parameters such as farmers' income growth rate and fund investment rate and their linkage growth are conducive to enhance the sustainability of rural pension, while the increase or decrease in the pay time of the pension has uniform affected on the sustainability of rural pension, their combined growth has a positive effect on long-term sustainability of the rural pension. This research has the important theoretical significance and practical value to rich and develop the theory and method of rural pension actual modeling and simulation and to improve system and policy of rural social security.

Key words: rural pension, sustainability, simulation, actuarial models, parameters adjusting