This study aimed to determine the effectiveness of the group play therapy on the insecure attachment and social skills of orphans in Ahvaz city. Statistical population included all orphans in Ahvaz city, of whom 30 students were selected whose scores in insecure attachment and in social skills were one standard deviation higher and one standard deviation lower than the mean, respectively and they were randomly divided into two treatment (15 persons) and control (15 persons) groups. The research tools included Randolph Attachment Disorder Questionnaire (2000) (RADQ) and Social Skills Rating System (SSRS) questionnaire (Gresham and Elliot, 1990). This is an experimental study with pretest, posttest, and follow-up by the control group. Firstly, pretest was implemented for both groups, and then experimental intervention (play therapy) was carried out for the treatment group during 10 sessions. After the therapeutic program, the posttest and two months later follow-up were implemented. The results obtained using the statistical method of multivariate covariance analysis showed that group play therapy reduces the insecure attachment and increases the social skills at P < 0.001 during the stages of posttest and follow-up in the treatment group compared to the control group. Results also indicated that there is a significant difference between posttest and follow-up of the treatment and control group in terms of the components of social skills (collaboration, assertiveness, and self-control).