The aims of this Study has been undertaken to build ap a group counseling program in developing optimism and reducing pessimism on delinquent juveniles of House reform and rehabilitation in Central Prison of Samail. The researcher of this study depended on basic method by implementing a group to reveal the effectiveness of the group counseling program in developing optimism and reducing pessimism in delinquent juveniles in Central Prison. The study involved a group of ( 15) young delinquent juvenile who received this program that was founded to achieve the aims of this study, The group counseling program was based on ration treatment and behavioral therapy for Albert Ellis. It was indicative of 12 counseling sessions that were carried out by two sessions per week. Each session ranged from ( 45- 90) minutes. The results of willcoxon test showed that there are differences with statistical significant (0.05≤ α) among the experimental group members in optimism and pessimism degrees on the two measurements: tribal and posttest. This reflects the effectiveness of the group counseling program that was used in this study. The results also showed that there are no differences with statistical significant on the statistical level (0.05≤ α) in optimism and pessimism degrees on the two measurements, the posttest and the follow up. This indicates the same thing that this program is very effective in developing optimism and reducing pessimism.