AIM:To investigate the importance of elbow 3D computed tomography in surgical planning when deciding on the treatment surgical treatment method of the ulnar nerve entrapment in the cubital tunnel. MATERIAL and METHODS: In this study, 21 patients with cubital tunnel syndrome in our clinic were included and retrospectively analyzed. All of the patients were diagnosed with EMG, and surgical planning was performed based on the anatomy of the cubital tunnel diagnosed via 3D computed tomography. In addition to the classical simple decompression of the ulnar nerve, 15 patients underwent cubital tunnel reconstruction with high-speed drill, whereas 6 patients underwent ulnar nerve anterior subcutaneous transposition. The results were evaluated based on the modified Wilson & Krout criteria. RESULTS: Fourteen of the patients were female and seven were male. The average age was 42.2 years. Fifteen patients underwent simple decompression of the ulnar nerve and cubital tunnel reconstruction. Transposition was performed in six patients. The patients were followed up for an average of 107.5 months (3-144). Based on the Wilson & Krout criteria, excellent results were obtained in 14 patients (66.7%), good results in 6 (28.6%), and poor results in 1 (4.8%). CONCLUSION: The evaluation of the cubital tunnel via 3D computed tomography before the operation is effective in determining the optimal surgical technique and obtaining more successful clinical results. The cubital tunnel reconstruction in addition to simple decompression increases surgical success and minimizes complications and the possibility of relapse due to the fact that the nerve remains in its natural position.