Chronic diseases are significant problems in South Africa. Chronic diseases' treatment outcomes are critical to the reduction of morbidity and mortality. There is limited data in South Africa on alcohol use and treatment outcomes of chronic diseases in older people. Understanding the association between alcohol use and chronic diseases treatment outcomes would inform potential interventions to address the duo. We analysed data from wave 1 of the Health and Ageing in Africa-a longitudinal Study in an INDEPTH community (HAALSI) study. We performed descriptive analysis to determine the prevalence of optimal chronic diseases' treatment outcomes (suppressed HIV viral load, normal blood pressure and normal blood sugar- euglycemia) and applied modified Poisson regression to determine the association between alcohol use and chronic diseases' treatment outcomes. The prevalence of optimal treatment outcomes was 87.4% suppressed viral load for those living with HIV, 42.7% normal blood pressure for hypertensives, 53.6% with euglycemia among diabetics and 52.4% with normal outcome parameters among those with multimorbidity. Alcohol use did not negatively impact the optimal treatment outcomes for HIV (aRR = 1.00, 95%CI 0.93-1.09), hypertension (aRR = 0.88, 95%CI 0.68-1.14), diabetes mellitus (aRR = 0.73, 95%CI 0.44-1.22), and multimorbidity (aRR = 1.00, 95%CI 0.93-1.09). Alcohol use was not significantly associated with treatment outcomes possibly due to underreporting of alcohol use. There is need to incorporate objective alcohol measurements and alcohol interventions in chronic diseases care settings. Furthermore, there is urgent need to strengthen the management of hypertension and diabetes, by adopting the strategies deployed for HIV management.