Population aging is one of the practical problems that need to be addressed in the new era. The construction of old-age service system is very important in Chishui City Which is regarded as a longevity town and tourist city in China. The results show that the proportion of the elderly population in Chishui City is 17.7 percent，which shows the characteristics of fast speed，aging and large population. Children support，labor income and retirement pension are the main economic sources of the elderly population. There are three problems in the construction of the old-age service system. In view of the above situation，this paper puts forward three countermeasures and suggestions，and gives good enlightenment and case study for the construction of Beijing’s pension service system.