Purpose: This study was conducted to investigate the relationship between uncertainty in illness and the future, sick role behavior with what diet, weight control, no smoking, abstinence, doctor visits, medications, etc, and quality of life of rehospitalized patients after percutaneous coronary intervention in a cardiology ward. Methods: A total of 120 patients participated in the study. Data were collected using a questionnaire and analyzed using t-test, ANOVA, $Scheff{\grave{e}}$ test, and Pearson's Correlation Coefficient. Results: The mean score for uncertainty was $3.45{\pm}1.08$. Sick role behavior of the patients showed a moderate value with a mean of $3.68{\pm}0.79$. The mean score for quality of life was $3.52{\pm}0.64$. Uncertainty in illness and the future was significantly correlated to sick role behavior with that diet, weight control, no smoking, abstinence, doctor visits, medications, etc (r=-.27, p=.002), and quality of life (r=-.35, p<.001), and sick role behaviors were significantly correlated to quality of life (r=.62, p<.001). Conclusion: The results implicate that there is a need to decrease the levels of uncertainty and reinforce positive behaviors by patients in order to improve their quality of life.