To assess the mental health and experience of sport-related harassment and abuse of elite aquatic athletes and to analyze it in relation to gender and discipline.Cross-sectional study using an anonymous survey.The FINA World Championships 2019.Registered athletes in the disciplines of swimming, diving, high diving, water polo, artistic swimming, and open water swimming.Athletes completed an online or paper-based questionnaire.The main outcome measures included screening for depression (10-item version of the Center for Epidemiological Studies Depression Scale revised), eating disorders (Brief Eating Disorders in Athletes Questionnaire), the subjective need for psychotherapeutic support, and the experience of sport-related harassment and/or abuse.A quarter (24.6%) of the 377 responding athletes were classified as depressed and 2.5% as having an eating disorder. More than 40% of the athletes stated that they wanted or needed psychotherapeutic support. Fifty-one athletes (14.9%) had experienced harassment/abuse in sport themselves, and 31 (9%) had witnessed it in another athlete. The experiences of harassment and abuse ranged from unwanted comments about body or appearance (40.2%) to rewards in sport for sexual favors (2.5%) and rape (0.3%). Athletes who had experienced harassment/abuse in sport themselves had higher average scores for depression and eating disorders, and more of them felt they needed psychotherapeutic support. Up to a third would not talk or report to anybody if they saw or experienced harassment/abuse, and less than 20% would talk to an official for help.Targeted initiatives are required to address mental health issues and harassment and abuse in sport in the FINA aquatic disciplines.