To investigate the treatment effectiveness between ultrasound-guided and blind injection techniques in the treatment of subacromial bursitis. A total of 40 patients with sonographic confirmation of subacromial bursitis were recruited into this study. These patients were divided into blind and ultrasound-guided injection groups. The shoulder abduction range of motion was compared before injections and 1 wk after the completion of injections in both groups. The shoulder abduction range of motion before injection in the blind injection group was 71.03 +/- 12.38 degrees and improved to 100 +/- 18.18 degrees 1 wk after the injection treatments. However, the improvement did not reveal significant statistical differences (P > 0.05). The shoulder abduction range of motion before injection in the ultrasound-guided injection group was 69.05 +/- 14.72 degrees and improved to 139.29 +/- 20.14 degrees 1 wk after the injection treatments (P < 0.05). Ultrasound may be used as an adjuvant tool in guiding the needle accurately into the inflamed subacromial bursa. The ultrasound-guided injection technique can result in significant improvement in shoulder abduction range of motion as compared with the blind injection technique in treating patients with subacromial bursitis.