The present study aimed to assess the prevalence and characteristics of child sexual abuse (CSA) in a nationally-representative sample of Slovak late adolescents. Randomized cluster sampling plan was used to sample 2186 secondary school students in their final school year with mean age of 18.6 years (SD = 0.7 years). The study employed the Child Sexual Abuse Questionnaire (Mohler-Kuo et al., 2014) consisting of multiple behavior-specific questions. The prevalence of CSA was analyzed separately for three clusters of CSA and gender. The self-reported lifetime prevalence of at least one form of CSA was 47.3% among girls and 22.0% among boys. The prevalence of noncontact forms of CSA was 40.6% among girls and 17.7% among boys. CSA with physical contact without penetration was reported by 30.2% girls and 11.6% boys. The prevalence of CSA with penetration was 5.6% among girls and 1.3% among boys. More than half of CSA occurred between 16-18 year of age in all three CSA cluster types. The severity of abuse was positively associated with the acquaintance with the perpetrator. Roughly 43-56% disclosed the abuse to another person. The majority of disclosed CSA was revealed to peers and partners. Negligible proportion of CSA instances were reported to the police. The results show that CSA is a widespread and considerably covert phenomenon within the population of Slovak late adolescents. Prevention activities should consider broad spectrum of CSA forms in order to counteract tendencies to associate CSA only with unwanted sexual intercourse.