This study explores the relation between gender differences and sexuality among young Hispanic people. Eight hundred and forty young people from Spain and Mexico filled out a self-administered questionnaire about sexuality (sexual experience, sexual orientation, and sexual relationships) and gender (self-identification). Men in both Spain and Mexico more commonly report the practice of masturbation and vaginal sex, and are more likely to be unfaithful than women. Women in both countries report more steady partners and longer length of relationships. There were greater gender differences for Mexican men and women than for Spanish men and women in terms of sexual frequency, sexual orientation, and infidelity. Therefore, gender may play an important role in young people's sexuality, more so in Mexico than in Spain.