The purpose of this study was to investigate the influence of relative factors on regular physical activity among Taipei city police officers. A total of 396 police officers at Taipei City Police Department were selected using a stratified random sampling method. Information about demographic characteristics, worksite environment, social psychological factors as well as the type, duration, frequency, and intensity of physical activity was collected through a self-administered questionnaire. Data were analyzed by descriptive statistics, chi-square test, analysis of variance, correlation, logistic regression, and multiple regression. The results showed that only 21.3% of the police officers performed regular physical activity. Work shifts and perceived exercise barriers were predictors of regular physical activity. Self-efficacy, perceived health status, perceived exercise barriers and benefits were predictors of physical activity level. Rates of regular physical activity are low among Taipei City Police Officers. It is therefore recommended that work shifts and social psychological factors should be valuable for developing a physical activity health promotion program.