Background: By the end of 2015, epidemiological studies approximated 37 million people living with HIV (PLHIV) and 46.3% of them were initiated to antiretroviral therapies. From the 90-90-90 strategy, by 2020 at global level, 90% of all people living with HIV were expected to suppress viral load (VL). Although VL suppression is an important indicator of treatment success in PLHIV, studies on this indicator remain scarce in Rwanda where the prevalence of HIV is 3% with 9% for non-suppression. This work, thus, determined the prevalence of VL non-suppression and its associated predictors among PLHIV.Methods: A cross-sectional study was conducted among 637 PLHIV enrolled in healthcare services between 2016 and 2017 in Nyaruguru district. Socio-demographic, treatment, clinical, immunological and VL data were extracted from medical records. Bivariate and multivariate logistic regression analyses were performed to determine associated factors with VL suppression consider-ing 95% confidence intervals and statistical significance of p<0.005.Results: More than half of participants were female (57.77%). The prevalence of unsuppressed HIV VL was 8.9% and 88.7% of respondents were satisfied with the service provided. Males were more likely to be unsuppressed HIV VL [aOR = 3.02; 95% CI (1.19-7.64), p = 0.02] than females. Higher likelihoods of VL non-suppression were among those with history of clinical failure [aOR = 3.14; 95% CI (1.70-14.03), p = 0.034] or history of treatment interruption [aOR = 8.29; 95% CI (2.60-26.42) p = 0.002]. Those with a bad perception toward the whole life treatment were more likely to be unsuppressed [aOR = 4.32; 95% CI (1.98-18.99), p = 0.049] than their counterparts.Conclusion: Sex, treatment interruption, bad perception toward the whole life treatment, clinical failure and lack of confidentiality were the major predictors of being unsuppressed. More efforts on counseling HIV patients to improve their knowledge would drop levels of VL non-suppression, so improving the quality of service should be prioritized to increase suppression.