BackgroundHIV/AIDS remains a major public health problem. Practice of risky sexual behaviors is the major effective driver of the HIV epidemic among HIV-positive individuals. This behavior exposes their partners to HIV, and for those that are already positive it exposes them to a risk of suprainfection by other strains.ObjectiveThe aim of this study was to assess the prevalence of risky sexual behavior and associated factors among people living with HIV attending antiretroviral therapy (ART) clinic at Nekemte Referral Hospital.MethodsAn institution-based based cross-sectional study was conducted at the ART clinic of Nekemte Referral Hospital from March to April 2016. A total of 337 people living with HIV on ART for at least 3 months were selected by consecutive sampling technique. Data were collected through face-to-face interview. Data were entered into Epi-data Version 3.1 and analyzed using SPSS version 20. Variables significant on bivariate logistic regression analysis at p<0.25 were considered as candidates for the multivariable logistic regression analysis, and statistical significance was set at p<0.05.ResultsApproximately one third (32.9%) of the study participants were engaged in risky sexual behavior in the past 3 months prior to the study. Having multiple sexual partners (adjusted odds ratio [AOR] =6.38, 95% CI: 1.65, 24.74), being with a positive sero-status partner (AOR =2.68, 95% CI: 1.31, 5.5), not disclosing sero-status (AOR =5.99, 95% CI: 1.36, 26.35), having a desire for a child (AOR =2.6, 95% CI: 1.5, 4.51), having experience of perceived stigma (AOR =2.63, 95% CI: 1.5, 4.62), and lack of education on importance of protecting self from strain (AOR =5.64, 95% CI: 3.19, 9.96) were significantly associated with risky sexual behavior.Conclusion and recommendationThe prevalence of risky sexual behavior was high, and approximately one third of study participants were engaged in risky sexual behavior. Efforts to increase awareness through health education and counseling are highly recommended.