Background: The research examined the effect of a scapular stabilizing exercise on shoulder pain, active range of motion (AROM) and changes in the position of the shoulder blade of patients with frozen shoulder. Methods: General physical therapy and a scapular stabilizing exercise were applied to a 53-year-old female patient with frozen shoulder three times a week for four weeks. Before and after the therapy, measurements were made on the visual analog scale (VAS) and of the AROM, and a lateral scapular slide test was conducted. Results: Following the therapy, VAS fell from 7 to 3. Before therapy, flexion, abduction, internal rotation, and external rotation recorded $133^{circ}$, $102^{circ}$, $45^{circ}$, and $53^{circ}$ respectively; after the therapy they increased to $150^{circ}$, $123^{circ}$, $55^{circ}$, and $65^{circ}$ respectively. The lateral scapular slide test showed sliding distances before therapy of 8.5cm at $0^{circ}$, 9.2cm at $45^{circ}$, and 11.3cm at $90^{circ}$; after therapy, the distances decreased to 6.8 cm at $0^{circ}$, 8.2 cm at $45^{circ}$, and 9cm at $90^{circ}$. Conclusion: The scapular stabilizing exercise was effective in alleviating shoulder pain, increasing AROM, and reducing changes in the position of the shoulder blade of frozen shoulder patients.