Self-esteem and lack of social phobia are considered amongst the components of mental health. These features are more likely to be created during the early years of life like any other mental aspect. Hence, the present research aimed to investigate the effectiveness of cognitive-behavioral play therapy in self-esteem and social anxiety of student. The statistical population included all the students in Tehran, from whom a sample of 24 was drawn through multi-stage cluster sampling. They were randomly assigned into the experimental and control groups. The data gathering tools included Rosenberg's Self-Esteem Scale and Connor Social Phobia Inventory. The experimental group underwent the group play therapy while the control group received no treatment. The findings indicated that group play therapy was effective in the increase of self-esteem and decrease of social phobia among the students. Therefore, it is recommended that children’s counseling and therapy centers as well as school officials employ the necessary interventions to enhance health, improve self-esteem, and decrease social phobia with regard to the necessary constructs for the improvement of children’s and adolescents’ mental health.