Introduction Reduced upper extremity function after stroke has previously been reported in 70-80% of patients with stroke in the acute stage and is one of the most common impairments after acute stroke impaired motor function, both in upper and lower extremity, influence the stroke unit care and planning of the rehabilitation, partly due to the economic costs. There is limited information in upper extremity function within the first days after a stroke. Prior studies include either both first and recurrent stroke or only one type of stroke. Objectives To investigate the frequency impaired arm and hand function in an unselected group of patients with first occasion of stroke. Method All patients at a stroke unit at Sahlgrenska University Hospital were assessed during 18 months. From the hospital records, the patients were identified, the patient charts were read and first stroke diagnosis was confirmed (by either imaging or clinical assessment). Impaired upper extremity function was defined in the following manner: assessed with the Modified Motor Assessment Scale (M-MAS UAS -95) by physiotherapist working at the stroke unit within 72 hours after stroke onset or if this was found in the patients chart, other standardized assessments of upper extremity function performed by the physical therapist, the occupational therapist or the physicians on the ward. Results During the study period 984 patients with first ever stroke (438 women 44.5%) were admitted to the stroke unit. A total of 213 patients were not at the stroke unit within 72 hours after onset and therefore excluded; 90 patients had unclear stroke onset time, 49 patients were located at another ward, 36 patients were in the intensive care unit, 25 in other hospitals in Sweden and 12 patients were hospitalized in another country. There were 771 patients over 18 years old at the stroke unit within 72 hours after stroke onset. Of these 56 patients (7.3%), were not living in the catchment area and therefore excluded. Of the 715 patients living in the geographical catchment area, 58, (8.1%) hade other upper extremity injury prior the stroke onset. Of the remaining first ever stroke patients (n=657), 311 patients (47.3%) hade impaired arm and hand function within 72 hours after stroke onset. Conclusion The frequency of impaired upper extremity function in this unselected population of first occasion of stroke is lower than previously reported. The Copenhagen stroke study noted 69 % impaired at admission and 43 % at one week. This indicates that today’s stroke patients present less frequent with impaired motor function in the upper extremity. However, they may have difficulties in functional activities which may influence content of rehabilitation process.