Boosting the employment of the older population is key to a healthy social security system in the era of population aging. Based on the China Health and Retirement Longitudinal Study，we find that the employment rate of urban Chinese falls sharply after reaching statutory retirement ages while the rural population stays in the labor force much longer，implying a high level of excess work capacity among the urban population. The plight of overwork among rural residents is also evident from their longer working hours. Among the major determinants of older employment are health，family support，and pension incomes. Rural residents postpone the exit from the workforce because of their inadequate savings and low pension receipts. Compared to their urban counterparts，rural workers are more concentrated in the agricultural sector and more likely to be self-employed. Policy responses to population aging should encourage higher employment among older urban people via a flexible retirement system while bolstering economic support for rural elderly to allow them to enjoy a retirement life as well.