Aims: To estimate the prevalence of diagnosed Type 2 diabetes mellitus in Greenland and to evaluate the quality of the diabetes care before and after implementation of a new diabetes programme. Methods: In this observational and cross-sectional study, data from the medical records were collected in Greenland in 2008 and 2010. Information about age, gender, most recently measured HbA(1c) , blood pressure and serum cholesterol and from the examination of eyes, feet and urine was obtained. The prevalence was estimated using the whole adult population in Greenland as background population. The quality of the diabetes care was monitored by six processes: three biological and three treatment indicators. A diabetes concept based on national guidelines, systematized recording in an electronic medical record and feedback to the clinics were used to improve diabetes care. Results: Four hundred and sixty-five patients were included in the 2008 sample and 691 in the 2010 sample. The total prevalence increased from 2.3 (95% CI 2.1-2.5) % in 2008 to 2.7 (95% CI 2.5-3.0) among Greenlanders aged 40 years old or above, corresponding to an increase of 19% (P = 0.006). All process indicators improved significantly between the two observations. Conclusions: Along with an increasing prevalence of diagnosed Type 2 diabetes, all six process quality indicators increased. It is strongly recommended that focus on the quality of diabetes care in Greenland should be maintained in order to benefit from the programme in the longer term.