Background: The great saphenous vein (GSV) is a continuation of the dorsal venous arch in the foot. It travels anterior to the medial malleolus and ascends in the superficial fascia along the medial aspect of the lower extremity and drains into the deep system via the saphenofemoral junction. The aim of this work was to compare between Radiofrequency ablation and mechanochemical ablation of GSV reflux regarding post operative pain, pigmentation, ulcer, hospital stay and rapid return to work. Methods: This was a prospective randomized clinical trial that was conducted on 60 patients diagnosed with GSV reflux in Department of surgery - vascular unit of Benha University Hospitals to compare between radiofrequency ablation and mechanochemical ablation. Patients were divided into two groups: Group A: 30 patients who were treated with mechanochemical ablation, Group B: 30 patients who were treated with radiofrequency ablation. Results: There was no significant difference in post-operative outcomes (recovery time, return to work and failure of procedure) between the studied groups. There was no significant difference in postoperative complications between the studied groups. In follow up, there was no significant difference in VCSS and patient satisfaction between the studied groups. But VAS Score was significantly higher in RFA group than MOCA group. Conclusion: Mechanochemical ablation is associated with less postoperative pain compared with Radiofrequency ablation. Although Pigmentation after procedure was significantly higher in Mechanochemical ablation group than Radiofrequency ablation group, Mechanochemical ablation and Radiofrequency ablation are both related to an improvement in quality of life.