This study investigated the relationship between physical activity during leisure time and perceived stress among working adults (N = 32,229). Data were gathered on physical activity, perceived stress, current health status, age, gender, life changes, ongoing problems, number of techniques used for stress reduction, and number of personality traits related to Type A behavior. To control for confounding variables Mantel-Haenszel summary risk estimates were used. Employees who expended more than 3.0 Kcal/kg(-1) . day(-1) in physical activity during leisure time were 0.78 and 0.62 times less likely to have moderate and high perceived stress, respectively. Working adults participating in moderate amounts of these activities have about half the rate of perceived stress as nonparticipants.