BACKGROUND: Zimbabwe has one of the highest HIV prevalence rates in the world. HIV treatment was initiated in 2004 and expanded to 94% coverage rate by the 2020. OBJECTIVES: i) to determine the level of treatment adherence during COVID-19-induced lockdowns and ii) to investigate the key determinants of adherence to ART during COVID-19-induced lockdowns. METHODS: The cross sectional study involved 392 people living with HIV (PLHIV) and was conducted at nine health facilities in Bulawayo City. Data was analysed using the Shapiro-wilk test for normality, Chi-squared test, Kaiser-Meyer-Olkin (KMO), Bartlett's test, exploratory factor analysis, reliability analysis, scree plot, correlation analysis and multiple linear regression analysis. RESULTS: 94.6% of the respondents took their ARTs on time, and 90.6% did not miss any treatment review. The factors influencing treatment adherence were health systems (beta value 0.334), Family support (beta value 0.138) and knowledge/understanding of treatment (beta value 0.109). Health outcome concerns (beta value -0.194) and food security and livelihoods (beta value 0.191). CONCLUSION: Three factors had a positive impact on treatment adherence namely, functional health systems, family support, and knowledge or understanding of health treatment, while two factors namely health outcome concerns and food security and livelihoods negatively impacted treatment adherence.