Objective: To understand the epidemiological characteristics and differences of HIV-positive cases among 15-24 years old in Jiaxing city and provide evidence for the development of targeted prevention and control measures. Methods: A descriptive epidemiological method was used to analyze the data of HIV cases aged 15-24 reported in Jiaxing from 1999 to 2018. Results: A total of 375 cases of young HIV were reported in 1999-2018, with an average age of 21.29±1.90 years, of which 42 were students. The ratio of male to female was 2.47∶1. The proportion of foreign household registration was higher (76%, 285 cases). The proportion of off-campus youth cases in total cases showed a downward trend(χ2=8.26, P=0.00), but the proportion of student cases showed an upward trend(χ2=15.73, P<0.01). Off-campus youth cases were mainly heterosexual transmission(59.16%, 197 cases), and the students’ cases were mainly homosexual transmission(88.10%, 37 cases). There were significant differences in gender, age, household registration, education level, route of transmission, late detection, CD4 level and source of detection among students and off-campus adolescents(P<0.05). Conclusion The prevalence of AIDS in adolescents and students is worthy of attention. The characteristics of adolescents inside and outside the school are different. Targeted prevention measures should be taken to reduce the harm of AIDS to young people.