Abstract Background: Incisional hernia is a common complication following laparotomy and is the most common indication for reoperation. However, the optimal approach for its repair is still a matter of debate. Aim of Study: The aim of this study was to compare between sublay and onlay mesh repairs in treatment of inci-sional hernia regarding the operative technique and post-operative complications. Patients and Methods: This prospective comparative study was conducted in General Surgery Department at Al-Zahraa University Hospital and Damanhour Medical National Institute in the period between October 2018 and April 2020. It included 120 patients with incisional hernia who were randomly divided into two equal groups: A (treated with sublay repair) and B (treated with onblay repair). Results: The mean operative time in group A was 112.2 minutes and in group B was 98.2 minutes. The mean time of drain removal in group A was 5.9 days while in group B was 14.17 days. Seroma formation after drain removal was not recorded in any patients of group A while it occurred in 6 patients in group B (10%). The other postoperative complica-tions were comparable in both groups. During 6 months of follow-up, hernia recurrence occurred in 1 patient in group A (1.7%) and in 3 patients in group B (5%). Conclusion: Sublay mesh repair of incisional hernia is a good alternative to onlay repair. It is applicable to all sites of incisional hernia with a low recurrence rate and acceptable complication rates.