Knowledge on HIV spread is important in combating HIV/AIDS, however its impact can only be realized if put into practice. This study was carried out in a Higher Learning Institution in Moshi Township in Kilimanjaro Region to assess the level of awareness of university communities about HIV/AIDs and its link with practice of risky sexual behaviors (RSB). We have found an adequate level of knowledge on the spread, risk behaviors and methods for protection leading to attendance to voluntary testing and counseling by 61% of respondents. Conversely, we have observed great extent of practice of RSBs including early sexual debut (16.7 years), having multiple and extramarital partners, involvement in practices that lead to unprotected sexual intercourse. We report an obvious gap between knowledge and behavior. This study therefore recommends that serious operational interventions must be put in place targeting the most sexually active groups, the youth in preliminary schools to sensitize on RSBs and ways to avoid them before they are engaged in sexual activities.