Prenatal cocaine and alcohol exposures have been associated with a variety of adverse effects ranging from subtle neurobehavioral abnormalities to major malformations. In this study, we used the Porsolt swim test to assess the effects of prenatal cocaine and alcohol exposures on stress-related behavior. Pregnant Long-Evans rats were injected daily with 80 mg/kg cocaine HCl (SC) or 6.2–6.5 g/kg ethyl alcohol (PO) from gestation days 7–20 with half the dose given in the morning and the other half in the afternoon. Pair-fed and ad lib control groups were also used. One male offspring from each litter was evaluated in the Porsolt swim test at the age of 120 days. The alcohol and cocaine groups were less immobile (i.e., struggled more to escape) than the controls. These results suggest that prenatal exposure to either alcohol or cocaine can adversely affect behavior in stressful or fearful situations.