Introduction: The purpose of current study is to determine the effectiveness of individual and group cognitive-behavioral techniques in decreasing psychological symptoms in Prisoners.   Method: A total of 48 prisoners selected randomly and were allocated into three groups with equal size. 16 participants receiving individual cognitive-behavioral psychotherapy along with teaching cognitive-behavioral techniques and other 16 participants receiving only individual cognitive-behavioral psychotherapy. The last 16 participants were waited (Control group). Using GHQ and SCL-90 tests, as well as a diagnostic interview conducted by a psychiatrist based on DSM-IV-TR criteria before and after interventions, participants' psychological status were measured. Data collated was analyzed using multiple analysis of variance procedure.   Results: After applying cognitive-behavioral interventions, scores of prisoners in both experimental groups in indexes of GHQ and SCL-90 decreased (p