The evidence for negative influences of maternal stress during pregnancy on child cognition remains inconclusive. This study tested the association between maternal prenatal stress and child intelligence in 4,251 mother–child dyads from a multiethnic population-based cohort in the Netherlands. A latent factor of prenatal stress was constructed, and child IQ was tested at age 6 years. In Dutch and Caribbean participants, prenatal stress was not associated with child IQ after adjustment for maternal IQ and socioeconomic status. In other ethnicities no association was found; only in the Moroccan/Turkish group a small negative association between prenatal stress and child IQ was observed. These results suggest that prenatal stress does not predict child IQ, except in children from less acculturated minority groups.