Background: HIV/AIDS is a disease of human immune system caused by HIV Virus. Adolescence is a phase of physical growth and development accompanied by sexual maturation, often leading to intimate relationships. Prevention of HIV infection primarily through safe sex and needle exchange programmes is a key strategy to control the spread of the disease.

Materials and Methods: A comparative study to assess the knowledge on HIV/AIDS and its prevention among adolescents in selected urban and rural higher secondary school of West District, Tripura with a view to develop health educational pamphlet”. In this study the data were collected from 86 no. of adolescents (42 no. of adolescents in urban higher secondary school of Dukli and 44 no. of adolescents in rural higher secondary school of Suryamaninagar, West District, Tripura) by using consecutive sampling technique. Method: self-administered structure knowledge questionnaire on HIV/AIDS and its prevention was used to collect data. Collected data were analysed by using descriptive and inferential statistics.

Result: The mean knowledge score was 13.93, standard deviation was 2.81 among adolescents in urban higher secondary school and the mean knowledge score was 11.48, standard deviation was 2.85 among adolescents in rural higher secondary school. Mean difference was 2.45 and calculated unpaired ‘t’ value was 4.02, which was found significant at 0.05 level, (tabulated ‘t’ value =1.98 and df=84).  The analysis of variance (ANOVA) “F” value shows there was significant association between the knowledge score with selected demographic variables in the aspects of father’s educational status among adolescents in selected urban higher secondary school at 0.05 level of significance. Calculated “F” value = 2.79* (tabulated “F” value = 2.34, df between the group = 6, within the group = 35) and the analysis of variance (ANOVA) “F” value shows there was significant association between the knowledge score with selected demographic variables in the aspects of source of information among adolescents in selected rural higher secondary school at 0.05 level of significance. Calculated “F” value = 2.56* (tabulated “F” value = 2.34, df between the group = 6, within the group = 37).