Background: Proprioceptive neuromuscular facilitation (PNF) has been proven effective in a myriad of clinical fields as a treatment to restore function in patients with musculoskeletal disorders, damage to the central nervous system, or sports injuries. Objectives: The purpose of this study was to investigate the effect of a 2-week PNF exercise intervention on the degree of calcification, pain perception, and shoulder joint function in persons with calcific tendinitis (CT) of the supraspinatus. Design: Matched pairs design. Methods: This study was classified into a PNF group (n=8) and a control group (n=7) through a matched pairs design. Filmed x-rays, Visual Analogue Scale (VAS), Simple Shoulder Test (SST), and Constant-Murley Scale (CMS) were used to assess the long and short axis of calcified deposits, self-awareness of pain, and shoulder joint function of the subjects. 8 participants in the PNF group received a scapular and upper extremity PNF exercise intervention for 30 minutes per session, 10 times/week for 2 weeks while no intervention in the control group. Results: Two-way repeated analysis of variance (ANOVA) showed a significant improvement after the 2-week PNF exercise intervention on calcified deposits, pain, and shoulder joint function (P<.05), whereas no changes in the control. Conclusion: These findings suggest that the intensive 2-week PNF exercise may maximize intervention effects to reduce calcified deposits and pain in a relatively short period time and is effective for restoring shoulder function without combining other treatments or exercises in patients with supraspinatus CT.