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This study aimed to evaluate the direct and interactive effects of socioeconomic status and birth weight on Tehran children motor proficiency. : The present study was a cross-sectional research which conducted in April and May of 2016 and the study population included 4/5 to 6-year-old boys and girls with very low and normal birth weight from 2 and 19 districts of Tehran city that from which 132 children were selected through a  convenience sampling. In this research we used socioeconomic status questionnaire and Bruininks-Oseretsky -2 test.  obtained data were analyzed using two-way ANOVA. The results showed that motor proficiency in children with very low birth weight was lower than those with normal birth weight (P <0/001), and in terms of effect of socioeconomic status, results showed that motor proficiency of children with low socioeconomic status was lower than those with high socio-economic status (P <0/001) and there wasn’t any significant relationship between effect of weight on motor proficiency with effect of SES on motor proficiency (Interactive effects )(P = 0/633). Results of the study showed that high socio-economic status had the capability of adjustment the negative effects of low birth weight on motor development. But it couldn't has a meaningful reparative effect. Thus the emphasis on the role of socioeconomic status on health of children with very low and normal birth weight is important. Also doing intervention such as improving the quality of environmental stimuli and taking care of pregnant mothers and also awareness for prevention of birth of low weight children must be considered in applied programs.