This study examines the sexual reproductive health (SRH) knowledge differential of unmarried adolescents in project and non-project sites run by the Family Planning Association of Bangladesh (FPAB). Secondary data from the “Reproductive Health and Family Life Education for Youth” project, implemented by the FPAB from the early 1980s until now to increase adolescents’ sexual and reproductive health knowledge, was used. The sample included 601 adolescents in project sites and 199 in non-project sites. Results from a multinomial logit regression reveal that adolescents in project sites had better knowledge than those in non-project sites although the difference was not pronounced. Additionally, adolescents’ knowledge in both sites is significantly affected by their sex, education, and place of residence. Therefore, this study suggests that appropriate BCC (Behavior Change Communication) materials with peer educators can be added to the existing project to increase adolescent knowledge and protect them from STIs including HIV/AIDS