Abstract: In the process of China's aging society, older people's basic needs are not met, then formed the ageing population crisis. In order to analyze the social mechanism of urban aged population crises, for in-depth analysis of typical cases in Beijing. Through document frequency method and literature of induction, ageing population crisis mechanism of social model is proposed. Through expert consultation method, improve the aging population crisis social mechanism model of Beijing. Through the questionnaire collection of discrete and continuous data information, verify the distribution characteristics of the two data, the use of R software to build structural equation model. The two-step least squares(DWLS)method is used to estimate the discrete data. The maximum likelihood method(ML method)is used to estimate the continuous data. The results show that social environment and social governance effect ageing population crisis obviously, effect of social environment than social governance, and social services, social economic is not obvious. The economy is the basis for solving the problem of aging work and the service is the guarantee to solve the problem of aging work. These two aspects have been greatly improved, so the old age groups pay more attention to social environment and social governance.