China's unprecedented population aging and social and economic change raise important issues concerning life course determinants of advantage or disadvantage into later life. Data from the China Health and Retirement Longitudinal Study (CHARLS) 2013 were analysed to identify the influence of childhood health on later life health as indicated by self-rated health and how this influence could be mediated by social and economic positions (SEP) and resources later in the life span. CHARLS provides nationally representative data on 18, 000 individuals aged 45 years and above in approximately 150 districts and 450 villages. Both multivariate logit regression model and KHB method (Karlson/Holm/Breen method) were applied to examine and decompose the life span influences on later life health. The results show that the childhood health, accounts for approximately half of the effect directly and another half of the effect indirectly through social and economic variations during adulthood. Relative living standard, marital status and urban residence are the most significant and important social and economic mediators for men; For women, living standard and secondary schooling are most influential while marital status is not significant. Implications for social and economic policies to improve later life health are discussed.