Abstract: Objective To understand the epidemiological characteristics of HIV infections in children aged 15 years in China and provide evidence for the development of AIDS prevention and control measures for children. Methods The demographic and transmission information of HIV/AIDS cases aged15 years diagnosed and reported at the end of 2015 were collected and the epidemic characteristics from 1985 to 2015 were analyzed. Results By the end of 2015,a total of 9 906 HIV/AIDS cases had been reported in children aged 15 years,the HIV epidemic in children can be divided into three stages: i.e. stage Ⅰ from 1985 to 1993,during which three cases infected by exogenous blood product use were found in 1985,and 2 local cases caused by intravenous drug use were found in 1994,stage Ⅱ from 1994 to 2009,during which increased local cases were found,especially 901 cases reported in 2009; and stage Ⅲ since 2010,during which the case number decreased steadily (842 cases in 2010,892 cases in 2011,842 cases in 2012,867 casesin 2013,840 cases in 2014 and 809 cases in 2015). Most cases were caused by mother to child transmission,accounting for 82.98%. The cases caused by homosexual and heterosexual transmission increased from 2 cases (0.24%) and 9 cases (1.07%) in 2010 to 26 cases (3.21%) and 19 cases (2.35%) in 2015,respectively. Conclusion The HIV epidemic in children aged 15 years in China began to increase along with the widespread of HIV infection in the country,but due to the prevention of mother to child transmission,the incidence of HIV infection in children showed a decline trend. However,sexual contacthas become the major transmission route of HIV infection in this population.