Objective To describe the characteristics of the HIV/AIDS epidemic in women aged 15-49 years in China. Methods HIV/AIDS cases from 2005 to 2012 that fulfilled the inclusion and exclusion criteria were identified on the Chinese HIV/AIDS case reporting system. Descriptive and spatial analyses were performed. Results A total of 103,559 female HIV/AIDS cases were included in our study. Based on the descriptive analysis, between 2005 and 2012, the proportion of heterosexually acquired HIV infection among women(15-49 years) increased rapidly from 35.8% to 87.4%. Approximately 60% of these cases were infected through non-marital heterosexual contact. Among older women(40-49 years), a slightly increasing trend was identified. The spatial analysis detected ‘hot spots’ in the Xinjiang, Yunnan, Sichuan, Guangxi, and Chongqing provinces. The epidemic trends in these areas were predominately driven by heterosexual transmission. Conclusion Non-marital heterosexual contact is a very important factor in the HIV/AIDS epidemic in women aged 15-49 years, and the HIV infection rate in older women is increasing. Several epidemic hot spots were detected in northwestern and southwestern China. Efficient interventions are needed to control the spread of HIV/AIDS among women living in these areas. Objective To describe the characteristics of the HIV / AIDS epidemic in women aged 15-49 years in China. Methods HIV / AIDS cases from 2005 to 2012 that fulfilled the inclusion and exclusion criteria were identified on the Chinese HIV / AIDS case reporting system. Based on the descriptive analysis, between 2005 and 2012, the proportion of heterosexually acquired HIV infection among women (15-49 years) increased rapidly The more than 60% of these cases were infected through non-marital heterosexual contact. Among older women (40-49 years), a slightly yet trend was identified. The spatial analysis detected ’hot spots’ in the Xinjiang The epidemic trends in these areas were predominately driven by heterosexual transmission. Conclusion Non-marital heterosexual contact is a very important facto r in the HIV / AIDS epidemic in women aged 15-49 years, and the HIV infection rate in older women is increasing. Several epidemic hot spots were detected in northwestern and southwestern China. Efficient interventions are needed to control the spread of HIV / AIDS among women living in these areas.