The present research examines how romantic relationship experience and age predict ambivalent sexism in adolescents. We measured sexist beliefs and romantic relationship experience in a large sample of Spanish adolescents (N=1447), ranging from 12 to 19 years of age. Consistent with prior research, age predicted less sexist beliefs. Controlling for the effects of age, relationship experience predicted increased hostile sexism in girls and increased benevolent sexism in boys. Additionally, younger boys (12-14 years) with greater relationship experience tended to endorse hostile sexism more strongly. The general decline in sexism over the course of adolescence masks a contrasting effect of romantic experience, which suggests that heterosexual adolescents' desire to attract romantic partners may foster, rather than reduce, sexism.