It's established that adherence rates to treatment are bad in chronic illnesses. The number of medicines prescribed and the rates of daily dosages have been shown to be of major influence for therapeutic compliance in AIDS or hypertension. Nevertheless, data on adherence to prescribed medications amongst diabetics are scarce. The aim of our study was to evaluate parameters influencing therapeutic compliance in type 2 diabetes. Adherence to treatment was evaluated by a questionnaire filled out during patient's hospitalisation in the diabetology department of a French general hospital of 450 beds. Factors influencing compliance were quantified taking into account demographic characteristics of our population, the treatments used, biological and medical data. 94 patients hospitalised for uncontrolled diabetes, aged 41-89 years, were studied. Non-adherence rate was high, 33 of them showed poor adherence to their drug treatment. Non-compliers were younger than compliant patients (56.5+/-12.1 vs. 65.5+/-12.5 years old; P<0.0001) and with a lower social position. Clinically, they were characterised by a shorter duration of diabetes and a lower number of clinical complications as macroangiopathy (6.9 vs. 33.3%; P=0.006). The number of daily doses or medicines didn't affect adherence rate. Improved control in therapeutic compliance may lead to better diabetic patients education. The implication is that instead of increasing the dose, changing the medication, or adding a second drug when glucose and HbA(1c)levels are high, clinicians should consider counselling patients on how to improve therapeutic compliance.