Background Prevalence of inadequate glycaemic control among patients with type 2 diabetes mellitus (T2DM)remains high. We assessed glycaemic control in the real-life practice among people with T2DM in metropolises in China who were treated with oral antidiabetic drugs (OAD) alone and to determine factors associated with inadequate giycaemic control in this population.Methods An observational, cross-sectional multicentre study was conducted in 16 metropolitan medical centers.People with T2DM who had been followed-up before the index visit which occurred from January to September 2007 were included in the study. All subjects were ≥30 years of age at the time of T2DM diagnosis and had received monotherapy or combination therapy of OAD for at least 6 months. Demographic and clinical data were collected from medical records. The main study outcome was the inadequate glucose control rate, which was calculated by the proportion of patients with haemoglobin A1c (HbA1c) ≥6.5% detected on the index visit.Results In this cohort of 455 patients with T2DM whose mean age was 60.6 years and mean disease duration was 6.1 years, 45.5% had inadequate glycaemic control. The mean (SD) HbA1c was 6.7% (1.3). Multivariate Logistic regression showed that physical inactivity, disease duration ＞10 years, body mass index (BMI) ≥24 kg/m2, low homeostasis model assessment of β-cell function (HOMA-β) index, less frequency of medical visit and hypertriglyceridaemia were independent determinants of inadequate glycaemic control. Higher incidence of self-reported hypoglycemia experience (47.1% vs. 34.8%, P=0.008) and more fear of hypoglycemia quantified by Worry subscaie of the Hypoglycaemia Fear Survey (HFS) Ⅱ were happened in subjects with good glycemic control.Conclusion Approximately one half of these outpatients with T2DM from the metropolitan medical centers in China had inadequate glycaemic control treated with OAD alone, which raises the need for more effective educational and therapeutic approaches on management of hypertriglycemia, enhancing physical exercise and weight control, and at the same time, lowering the hypoglycemic risk and diminishing the hypoglycemic fear of patients.