This article offers a systematic meta-analysis of 49 psychosocial studies conducted in the past ten years on the causes of addictive behavior in Iran. It examines the following variables with effects on substance abuse (ordered according to magnitudes of effect sizes based on Cohen’s interpretation: range=medium to small effects): quality of life skills and resistance to competency training programs; peer prod rug influence; knowledge about substance abuse; parent-child interaction and family bonding; psychological and personal factors; displacement and migration; age; parental monitoring and supervision; depression; knowledge; attitude and practice; occupation and economic activities; academic performance; modeling of drug use through film and cartoon; familial factors; father’s addiction; gender; father’s addiction and interpersonal conflict; co morbidity; history of familial drug use; increasing knowledge through poster and caricature; physical illness; SES; religious beliefs; psychological profile; increasing knowledge and awareness through film; father’s addiction and academic performance.