Sexually Transmitted Infections (STIs) remains a serious reproductive health problem globally. Despite this fact, youths recklessly involve in sexual activities which predisposes them to STIs which could rather be easily preventable. Therefore, the aim of this study was to evaluate the knowledge, attitude and practice of youths aged 19–24 towards prevention of STIs at KIU-TH in Ishaka Bushenyi district, Uganda. The study was a descriptive crosssectional and quantitative methods were employed in data collection. Fifty respondents both male and female were selected using a convenient sampling method. Most respondents 30 (60%) were between 19 – 20 years, 30(60%) were students and 30(60%) were single. Knowledge towards prevention of STIs was good as majority 50(100%) understood the term STIs, 25(50%) knew HIV infection as an STIs, 50(100%) knew about transmission of STIs, 30(60%) had been sensitized and health educated about STIs prevention and majority knew condom use 30(60%) as one of the ways of preventing STIs. Attitudes were fair as majority 40(80%) believed that STIs can be dangerous and majority 40(80%) felt they could prevent STIs. Practice was poor as majority had 1-2 partners, 30(60%) and majority had their first partner at 15-17 years old 30(60%), majority of the respondents took alcohol 35(70%), majority 37(74%) reported teenage involvement in sexual relationship and 35(70%) reported alcohol as one of the most leading factors into sexual relationships, majority 33(66%) did not take precautions during sexual intercourse only 18(36%) used condoms. The study found out adequate knowledge towards STIs prevention and attitudes were fair but practices were poor. Keywords: knowledge, attitude, practice, youth, sexually transmitted infections, Uganda