Gender differences in age at first onset, duration of untreated psychosis, psychopathology, social functioning, and self-esteem were investigated in a group of 578 young adults with a first-episode schizophrenia spectrum disorder. The mean age at first-onset of symptoms, age at first contact, and duration of untreated psychosis were similar for men and women. Men had more severe negative symptoms, poorer premorbid functioning, and poorer social networks, whereas women had more severe hallucinations. More men than women were substance abusers, were unemployed, and lived alone. Women had poorer self-esteem than men, in spite of better scores in functioning. Premorbid social adjustment was significantly related to the level of negative symptoms and number of friends. Conclusion is that men and women with first-episode psychosis showed different psychopathological characteristics and different social functioning, which cannot be explained by older age of onset for women. Women make more suicide attempts and experience lower self-esteem in spite of better social functioning.