OBJECTIVE: Rotator cuff calcific tendinitis (RCCT) is a benign but incapacitating condition and in some patients it is the cause of chronic debilitating pain and functional disability. We aimed to reveal the short-term effects of low-level laser therapy (LLLT) on clinical and sonographic parameters in patients with symptomatic RCCT. METHOD: This prospective randomized controlled study analyzed 76 painful shoulders of 68 patients aged 18-75 years, with over 3 months of shoulder pain and where RCCT was confirmed sonographically. Patients in the LLLT group (received 5 LLLT sessions per week and home exercises for 5 days/week for 3 weeks) and the control group (received home exercises, 5 days/week for 3 weeks) were assessed clinically and sonographically just before and after treatment, recording pain intensity, range of motion (ROM), shoulder functional status, location (supraspinatus/infraspinatus, subscapularis), number and degree of calcification. Degree of calcification was determined with ultrasound and classified by the Bianchi-Martinoli classification. The LLLT was applied to the calcified areas marked under ultrasound guidance. RESULTS: Both groups showed statistically significant improvements in ROM, pain intensity, shoulder pain and disability index (SPADI) pain/disability/total, and degree of calcification after treatment. No significant change was achieved for calcification in the control group. Considering the change values, improvements in abduction, extension, pain intensity, SPADI pain/disability/total, calcification number, and calcification degree parameters were found to be statistically significantly better in the LLLT group than in the control group. CONCLUSION: Adding LLLT to the home program in treatment of symptomatic RCCT outperformed the home program alone, reducing the number and severity of calcifications, improving pain and disability.