This study was conducted to evaluate the effectiveness of life skills training and group relaxation on the paranoid thinking of Imam Khomeini nurses in Shahrak. The statistical population of this study was all nurses of Imam Khomeini Hospital in Arak. From this population, 45 people were selected by convenience sampling and randomly divided into two experimental groups and one control group. Experimental group 1 received life skills training in 10 sessions of 45 minutes twice a week and experimental group 2 received light training in 10 sessions of 45 minutes twice a week. The Paranoid Thinking Scale (Green 2008) were the tools used in this study. Data obtained from the groups were analyzed at two statistical levels. In descriptive statistics, the frequency, mean and standard deviation of the data were, and in the second level, inferential statistics that the data due to having a pre-test, one-factor covariance and multivariate covariance were used. Then, Bonferroni post hoc test was used to compare the means by two. Both life skills and group relaxation approaches have a significant effect on the paranoid thinking of nurses at Imam Khomeini Hospital in Arak. A comparison of the two approaches showed that the life skills approach was more effective on paranoid thinking than group relaxation. Also, there is no statistically significant difference between the mean scores of post-test and the mean scores of follow-up test, which shows the stability of the results affected by therapeutic interventions over time.