Ambulatory blood pressure monitoring (ABPM) can detect phenotypes associated with increased cardiovascular disease (CVD) risk. Diabetes is associated with increased CVD risk but few data are available documenting whether blood pressure (BP) phenotypes, detected by ABPM, differ between individuals with versus without diabetes. We conducted a cross-sectional analysis of 567 participants in the Jackson Heart Study, a population-based study of African Americans, taking antihypertensive medication to evaluate the association between diabetes and ABPM phenotypes. Two clinic BP measurements were taken at baseline following a standardized protocol. ABPM was performed for 24 h following the clinic visit. ABPM phenotypes included daytime, sustained, nocturnal and isolated nocturnal hypertension, a non-dipping BP pattern, and white coat, masked and masked isolated nocturnal hypertension. Diabetes was defined as fasting glucose ⩾126 mg dl-1, haemoglobin A1c ⩾6.5% (48 mmol mol-1) or use of insulin or oral hypoglycaemic medications. Of the included participants (mean age 62.3 years, 71.8% female), 196 (34.6%) had diabetes. After multivariable adjustment, participants with diabetes were more likely to have daytime hypertension (prevalence ratio (PR): 1.32; 95% confidence interval (CI): 1.09-1.60), masked hypertension (PR: 1.46; 95% CI: 1.11-1.93) and masked isolated nocturnal hypertension (PR: 1.39; 95% CI: 1.02-1.89). Although nocturnal hypertension was more common among participants with versus without diabetes, this association was not present after adjustment for daytime systolic BP. Diabetes was not associated with the other ABPM phenotypes investigated. This study highlights the high prevalence of ABPM phenotypes among individuals with diabetes taking antihypertensive medication.