Background: Successful parathyroidectomy (PTX) with stable postoperative parathyroid hormone (PTH) levels is associated with the stabilization of coronary artery calcification score (CACS) in patients with severe secondary hyperparathyroidism (SHPT) undergoing hemodialysis. To use computed tomography (CT) to evaluate the influence of PTX on CACS in asymptomatic patients. Methods: This study was performed with institutional review board approval. Written consent was obtained from each patient. Forty-eight patients (mean age ± SD 54.50 ± 13.14 years; range 33–77 years) undergoing maintenance hemodialysis who underwent PTX and 56 patients (mean age 55.28 ± 12.32 years; range 35–76 years) who did not undergo PTX received prospective follow-up for 2 years. CACS was quantitatively performed using the Agatston method after CT scan. The differences between baseline and end-of-study PTX parameters were analyzed with the paired Student t test. Results: For patients who underwent PTX, mean square root of CACS did not increase from 23.16 ± 18.58 to 23.68 ± 18.16 (t = 1.846, p = 0.072) from baseline to follow-up. In patients who did not undergo PTX, mean square root of CACS increased from 20.21 ± 16.47 to 28.72 ± 20.95 (t = 10.110, p < 0.001) from baseline to follow-up. In addition, the median annual progression rate of CACS was lower among PTX patients (4.89%), compared with the marked annual progression rate of CACS in non-PTX patients (52.81%; t = 11.264, p < 0.001). Conclusion: Dysregulation of calcium and phosphate metabolism caused by SHPT may result in significant CAC progression in asymptomatic hemodialysis patients. Low PTH state after PTX may stabilize CAC progression in hemodialysis patients.