The purpose of this study was to assess the perceived exercise self-efficacy and exercise benefits/barriers of Korean adults with chronic diseases, and the relationship between the two variables. For the study, 249 Korean adults with chronic diseases with ages ranging from 18 to 79 years were recruited from hospitals or health centers in five Korean cities and surrounding rural areas. The research instruments were the scales that researchers psychometrically verified the Exercise Self-Efficacy Scale, developed by Bandura (1997), and the Exercise Benefits/ Barriers Scale, developed by Sechrist, Walker, and Pender(1987). Results of descriptive analysis showed that Korean adults with chronic diseases perceived relatively low exercise self-efficacy and relatively high exercise benefits/ barriers. Exercise self-efficacy was significantly correlated with gender, education, regular exercise, and exercise benefits/barriers was significantly correlated with gender, regular exercise. Pearson correlation coefficient showed the significant relationship between the two variables. Further researches, which are a study to evaluate a causal structure for Pender's Health Promotion Model and an intervention study to increase physical activity of chronic patients, are recommended.