To explore the feasibility and sub-group characteristics of current family support for elderly in China，this study utilizes synthesis evaluation from perspectives of both burden of elder care and capacity of family support. We design three sets of index from economic，human-resource and potential dimensions，and an integrated summary index，to identify the most vulnerable sub-groups. Data from CLHLS are used to develop and analyze the sets of index. Results suggest that the largest gap in family capacity relative to burden of elder care exists in the oldest old，the female old，and the old living in the east or middle area. These vulnerable groups in old-age support do have much lower family capacity with higher burden of care in all the economic，human resource and potential dimensions，and their inferiority can also be traced from past life experiences，which is getting worse as they are ageing.

Life expectancy is a comprehensive measurement of mortality,which essentially has a close and interactive relationship with mortality by age.The decomposition of life expectancy difference is a useful tool to study the regular pattern in changes of death mode.Pollard and Arriaga proposed two decomposition methods to explain life expectancy differences.This paper will introduce these two methods and apply them to China’s Life Table of 1990 and 2008.In addition,we compare the characteristics of the two decomposition methods,and provide recommendations for their applications.