Objective To analyze the efficacy and safety of ultrasound-guided modified percutaneous suction for the treatment of calcific supraspinatus tendinitis. Methods From January 2017 to January 2019, 60 patients with calcific supraspinatus tendinitis admitted to our hospital were selected as subjects. Patients in the control group underwent ultrasound-guided single-needle percutaneous suction. Patients in the observation group underwent ultrasound-guided double-needle percutaneous suction. The degree of pain was evaluated by numberal rating scale (NRS), the shoulder function and range of motion were evaluated using the university of California at Los Angeles shoulder rating scale (UCLA) and the Constant-Murley Shoulder Function Score System before and 3 days, 7 days, 1 month and 6 months after treatment. The results of DR examination and the ratio of second and third treatments were compared between the two groups. The incidence of adverse reactions during treatment and follow-up was also recorded to assess safety. Results There was no significant difference between the two groups before treatment (P>0.05). At 3d and 7d after treatment, the NRS score of the observation group was lower than that of the control group (P<0.05). At 1 month and 6 months after treatment, the NRS scores of the two groups were not significantly different (P>0.05). In terms of UCLA score and Constant-Murley score, there was no significant difference between the two groups before treatment (P>0.05). At the 3d, 7d, 1st, and 6th months after treatment, there was no significant difference between the two groups before treatment (P>0.05). The results of DR in the observation group showed that the calcifications decreased or disappeared at 7 days after treatment. The second and third treatment rates of the observation group were lower than the control group (P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups during treatment (P>0.05).Conclusion Although ultrasound-guided modified percutaneous suction for calcified supraspinatus tendonitis does not improve the shoulder function and range of motion, it can reduce pain in patients at an early stage, with significant therapeutic effects and good safety.