Prenatal environmental adversities may affect brain development and are associated with increased risk for schizophrenia, an illness with 50% comorbidity with addiction. Maternal immune activation by poly-inosinic–citidilic acid (Poly(I:C)) exposure can promote behavioral alterations consistent with schizophrenia symptoms in rodents. Considering the vulnerability to addiction in patients with schizophrenia, we evaluated the interactions between prenatal Poly(I:C) administration and addiction in two animal models (behavioral sensitization and conditioned place preference — CPP) in mice repeatedly treated with amphetamine (AMP). Additionally, stereotyped behavior and cross-sensitization with cocaine (COC) were also investigated. Swiss male mice offspring were submitted to prenatal administration of 5mg/kg Poly(I:C) in the 9th day of pregnancy. At the age of 90days, mice were treated with 2.5mg/kg AMP for 9days to evaluate behavioral sensitization or stereotyped behavior. Cross-sensitization with 10mg/kg COC was evaluated 24h after the last treatment day. For AMP-induced CPP evaluation, mice were treated during 8 consecutive days. Prenatal Poly(I:C) administration potentiated both AMP-induced behavioral sensitization and CPP. Furthermore, Poly(I:C) increased cross-sensitization with COC. Prenatal administration of Poly(I:C) is able to potentiate vulnerability to addiction in two animal models, without however modulating stereotyped behavior. •Maternal immune activation potentiated behavioral sensitization to amphetamine.•Maternal immune activation did not modify stereotyped behavior in offspring.•Maternal immune activation potentiated conditioned place preference to amphetamine.•Maternal immune activation increased amphetamine/cocaine cross sensitization.