OBJECTIVES: The National Healthcare Group Polyclinics (NHGP) is a group of 9 public sector primary care clinics in Singapore. This study examines the factors associated with poor glycaemic control in Asian patients with type 2 diabetes mellitus (T2DM) in Singapore. METHODS: This is a cross-sectional study of patients with T2DM who attended the same clinic in 2009 for the treatment of diabetes. Demographic characteristics, medical diagnosis, clinical parameters and laboratory results were extracted from the group’s Diabetes Registry (CDMS). Glycaemic (HbA1c) and cholesterol (LDL-c) control were compared with age and logistic regression analysis was applied to study the factors associated with poor glycaemic control using HbA1c cut-off at 8%. RESULTS: Among the 58,057 T2DM patients were more females (54%), disproportionately more Indians (13%) and fewer Chinese (71%) than the general population. Both HbA1c and LDL-c improved with age. The mean HbA1c decreased gradually from 8.16±1.74% (<40 years) to 6.94±0.99% (80+ years) while mean LDL-c dropped from 2.84±0.80 to 2.56±0.70. The Indian and Malay groups had significantly poorer glycaemic control compared to the Chinese, AdjOR 1.66 (95%CI:1.56-1.77) and 1.53 (95%CI:1.43-1.63) respectively. Other significant predictors of poor glycaemic control included the male gender (AdjOR 1.19; 95%CI 1.19:1.14-1.25), presence of maculopathy or retinopathy, peripheral vascular disease, coronary heart disease, heart failure, and being on insulin therapy (AdjOR 8.00; 95%CI:7.54-8.48). Patients with poor LDL-c (4.0+ mmol/L) were 4.2 times the odds of having poor glycaemic control (95%CI:3.78-4.66) while those with Grade 2 hypertension were 1.5 times (95%CI:1.35-1.76). CONCLUSIONS: Younger T2DM patients had poorer glycaemic and cholesterol control than older patients. Those with poor glycaemic control also had corresponding poorer cholesterol and blood pressure control. These patients had a higher lifetime risk of developing micro- and macro-vascular complications and should be treated much more aggressively to achieve “optimal” glycaemic and cholesterol control.