Background: Diabetes Mellitus is the commonest endocrine-metabolic disorder in Nigeria similar to the experience in other parts of the world. The aim was to assess the clinical and laboratory profile, and evaluate the quality of care of Nigerian diabetics with a view to planning improved diabetes care. Materials and Methods: In a multicenter study across seven tertiary health centers in Nigeria, the clinical and laboratory parameters of diabetic out-patients were evaluated. Clinical parameters studied include type of diabetes, anthropometry, and blood pressure (BP) status, chronic complications of diabetes, and treatment types. Laboratory data assessed included fasting plasma glucose (FPG), 2-h post-prandial (2-HrPP) glucose, glycated hemoglobin (HbA1c), urinalysis, serum lipids, electrolytes, urea, and creatinine. Results: A total of 531 patients, 209 (39.4%) males and 322 (60.6%) females enrolled. The mean age of the patients was 57.1 ± 12.3 years with the mean duration of diabetes of 8.8 ± 6.6 years. Majority (95.4%) had type 2 diabetes mellitus (DM) compared to type 1 DM (4.6%), with P < 0.001. The mean FPG, 2-HrPP glucose, and HbA1c were 8.1 ± 3.9 mmol/L, 10.6 ± 4.6 mmol/L, and 8.3 ± 2.2%, respectively. Only 170 (32.4%) and 100 (20.4%) patients achieved the ADA and IDF glycemic targets, respectively. Most patients (72.8%) did not practice self-monitoring of blood glucose. Hypertension was found in 322 (60.9%), with mean systolic BP 142.0 ± 23.7 mmHg, and mean diastolic BP 80.7 ± 12.7 mmHg. Diabetic complications found were peripheral neuropathy (59.2%), retinopathy (35.5%), cataracts (25.2%), cerebrovascular disease (4.7%), diabetic foot ulcers (16.0%), and nephropathy (3.2%). Conclusion: Most Nigerian diabetics have suboptimal glycemic control, are hypertensives, and have chronic complications of DM. Improved quality of care and treatment to target is recommended to reduce diabetes-related morbidity and mortality.