Purpose: This study was conducted to investigate the relations among gratitude, depression, and psychological well-being among clinical nurses. Methods: The participants were 411 clinical nurses, working in U city. Data were collected during the four months, April to June, 2012. Data were analyzed using descriptive analysis, t-test, ANOVA, Pearson correlation coefficients and multiple regression with the SPSS/WIN 20.0 program. Results: The mean scores for gratitude and psychological well-being were above average. The mean score for depression presented a probable depression level. Psychological well-being in clinical nurses was significantly correlated with gratitude (r=.55, p<.001) and depression (r=-.62, p<.001). The significant predictors of psychological well-being for clinical nurses were depression (β=-.47, p<.001) and gratitude (β=.34, p<.001), which explained 48.0% of the variance in psychological well-being. Conclusion: The results indicate that it is necessary to develop depression reduction and gratitude enhancement programs to improve the psychological well-being of clinical nurses.