Background: A child's psychosocial behavior may be significantly impacted by elements such as nutrition, physical exercise, and socioeconomic issues since they are crucial for healthy growth, development, and conduct. Objective: The aim of the current study is to assess the effect of after school physical activity, nutritional status and socioeconomic status on psychosocial behavior problems of primary school students. Subjects and methods: Two schools in Minia city were chosen randomly. Apparently healthy male students of the primary 6^th grade in both schools were included in the study. A structured questionnaire was applied to collect socio-demographic and nutritional data. Students from the first school (the active group) had 2 extra after-school physical classes for 6 months. Nutritional status assessment was carried out through measurements of weight and height. /Results: The studied sample included 88 male students; the active group included 42 students and the control group included 46 students. Almost half of each group belonged to families with low-educated mothers (52.3% in the active group vs 45.6% in the control group). Low-income families were more in the active group than in the control group (61.9% vs. 45.6%). The active group got a higher score than the control group (P<0.001), according to Physical Assessment Score. Students with psycho-social problems with a total score ≥15 according to PSC-17 were 16 (18.2%). Logistic regression analysis revealed that child order (P=0.02) and maternal education (P=0.024) were strong predictors of psychosocial behavior of children followed by physical fitness (P=0.03) and number of meals per day (P=0.05). Conclusions: Birth order, mother education, physical exercise and number of meals consumed per day are the most powerful predictors of psychosocial behavior of children.