This study, targeting the senior citizens of Kaohsiung city as the research subjects, examines the general conditions of their leisure preferences, participations, constraints, and the mutual relationship among these three factors. Otherwise, this study also explores the differences of leisure preferences, participations, and constraints between urban and rural senior citizens. For the empirical process of investigation, this study primarily executes the questionnaire surveys within the urban (Sanmin and Fongshan districts) and rural (Cishan and Meinong districts) areas, and then uses the analysis of reliability and validity, descriptive statistics, correlated analysis, regression analysis, independent-sample t test, and one-way ANOVA to discuss the abovementioned issues. The results show that (1) the highest chosen items within each type of leisure preferences, participations, and constraints for the urban and rural senior citizens are all similar. Watching TV, dining together, and gossiping are the most preferred activities for the types of recreation and social interaction, and the leisure constraints which they deal with are not severe. (2) There are significant correlations between leisure preferences and participations, and which some factors of leisure constraints would impact them. (3) Some personal attributes of surveyed subjects have brought significant differentiations for their leisure preferences, participants, and constraints. (4) There are significant differences of leisure preferences, participations, and constraints between urban and rural citizens.