Ho Chi Minh City Child Welfare Foundation and Danish-Vietnamese Association have carried out the project "For children survival at southern Vietnam provinces" with many objectives and activities including HIV / AIDS prevention programs Objectives To provide background data for the implementation of intervention programs, this study was conducted aiming at identifying the proportions of special circumstances adolescents having correct knowledge, attitude, and practices concerning HIV / AIDS prevention. Methods A descriptive cross-sectional study was carried out with 320 subjects aged 12 to 19 years old randomly selected at 6 blocks of wards 19 and 22.