To evaluate the results of the treatment with medium-energy extracorporeal shock wave therapy (ESWT) in rotator cuff calcifying tendinitis. Fifty-four non-consecutive patients, who were referred to our institute for rotator cuff calcifying tendinitis, were managed with a standardized protocol in four sessions of medium-energy (0.11 mJ/mm2) ESWT administered with an electromagnetic lithotriptor. Pain was evaluated at the end of each session, functional state of shoulder was assessed at 1 and 6 months after the end of procedure. All patients underwent radiographs and sonography imaging. No systemic or local complications. Thirty-eight patients (70%) reported satisfactory functional results. Radiographs and sonographs showed a disappearance of calcium deposit in 29 patients (54%) and in 19 patients (35%) it appeared to be reduced more than a half. A correlation was found between residual calcium deposit and the clinical outcome, but some patients showed a reduced pain without modification of calcium deposit. These results were unmodified at 6 months follow-up. Our protocol of medium-energy ESWT provides good results overall about pain modulation.