ObjectiveTo assess the incidence and predictors of hypertension among patients with diabetes attending a diabetes follow-up clinic.MethodsThis institution-based retrospective cohort study was conducted among patients with diabetes who attended a diabetic follow-up clinic at Asella Referral and Teaching Hospital between January 2017 and December 2021. Patients diagnosed with hypertension prior to diabetes, or diagnosed with hypertension at the start of follow-up, were excluded. Data were extracted from medical records and analysed.ResultA total of 351 patients with diabetes were included. The incidence density rate (IDR) of hypertension during 688.98 person-years of observation was 58.05 per 1000 (95% confidence interval [CI] 42.58, 79.14) person-years. The cumulative incidence of hypertension was 11.4% (95% CI 8.05, 14.7%) over 5 years. The 25th percentile survival time to hypertension development was 4.6 years. Multivariable Cox proportional hazard regression analysis showed that older age (adjusted hazard ratio [HR] 6.24, 95% CI 3.13, 12.45), family history of hypertension (adjusted HR 1.67, 95% CI 1.22, 9.65), comorbidity (adjusted HR 2.20, 95% CI 1.94, 5.21) and higher body mass index (adjusted HR 2.07, 95% CI 1.23, 5.63) were statistically significant predictors of hypertension development.ConclusionAmong patients with diabetes in Ethiopia, the IDR of hypertension was high; and older age, family history of hypertension, comorbidity and higher body mass index were statistically significant predictors of hypertension development.