OBJECTIVE This study investigates the role of customary activities, both social and solitary, in mortality among the oldest old in China. METHODS The data come from the Chinese Longitudinal Healthy Longevity Survey. Weibull hazard models analyze the mortality risk of those 80 years of age and older within a 2-year period between 1998 and 2000. RESULTS Results show that solitary activities, either active or sedentary, are significantly associated with lower mortality risk. The effect of social activities on mortality gradually diminishes with age and is reversed at very old ages when physical exercise, health status, and sociodemographic characteristics are controlled. DISCUSSION Customary activities, which are less physically demanding, show independent effects on the elderly's survival. Withdrawal from social contacts may be an adaptive response to challenges faced at very advanced ages. It is important to recognize the unique characteristics of this rapidly growing population.