Background & Aim: Every year, thousands of children admitted in foster care centers because of several reasons, neglect, physical abuse, parental substance abuse, divorce and social- economic poverty. In addition,  living in these centers causes a host of behavioral and health problems. In regard to this issue, mental health status of 7-11 years children living in foster care centre in Tehran was assessed.

Materials & Methods: we performed a cross sectional study with 105 children (57 boy, 48girl). In this research, sampling method was census. The required information about children's mental health was obtained by the child behavioral checklist (CBCL) from guardians who recognized these children on the basis of their behavior.

Results: Result have showed that most frequent type of behavioral problem in these children was as follows: Delinquent (%44/8), Externalizing (%40), Internalizing (%40), social problems (%13/3) and aggression (%11/4). Further more, the obtained total scores of questionnaire showed that more than %28 of these children had mental health problem. Ki- scoare test showed that there was a meaning full relation between problems related to attention and mental health with gender.

Conclusion: On the basis of these finding and results of researches in other countries, full attention and health facility should be given to these findings and the results of other studies, paying full attention, assessment and further studies on high risk groups of children are recommended.