This study aimed to estimate the self-reported prevalence of violence perpetration and victimization among Hong Kong youths and the associated health risk behaviors using a representative sample of 1,126 young adults aged 18-27 years. Perpetrating physical and emotional violence was common in Hong Kong, with prevalences ranging from 20.8% to 38.3% in males and from 6.4% to 21.3% in females. Victimization of physical and emotional violence was also common for both sexes, with prevalences ranging from 16.4% to 36.3% in males and from 6.6% to 19.2% in females. Perpetration of sexual harassment and sexual violence was less prevalent, whereas victimization of sexual harassment and sexual violence ranged from 0.6% to 3.6% in males and from 2.3% to 13.2% in females. Both violence perpetration and victimization among youths were significantly associated with substance use, risky sexual behaviors, and pregnancy. The implications of this study for violence prevention programs are discussed.