Background: Incisional hernias (IH) occur through a weakness at the site of abdominal wall closure. This may be laparotomy or laparoscopic trocar site incisions or parastomal hernia. This study aimed to evaluate the incidence of postoperative surgical site occurrence following component separation and onlay mesh hernioplasty for midline incisional hernias. Subjects and Methods: This prospective controlled clinical trial was conducted at the gastrointestinal tract (GIT) and laparoscopic surgery unit Faculty of Medicine at Zagazig University General Surgery Hospitals. The study included 30 patients of Incisional hernia (IH). Patients in this study were divided into two groups: Group (A) included 15 patients underwent component separation techniques (CST) and Group (B) included 15 patients underwent onlay technique. Results: the mean operative time in component separation group (114.6±20min) was longer than in onlay group (105.7±26.3min), without statistically significant difference p=0.64. The component separation technique was associated with significantly longer hospital stay compared to only mesh repairs (3±4.6versus 2±0.7; p<0.05). The only mesh repairs was associated with significantly longer time to drain removal compared to component separation technique (14±3.9 versus 10±4.67; p<0.05). The patients with only repairs takes significantly longer time to return to normal activity (97.0±3.8days) compared to those with component separation technique (69.2±6.0 days). Follow up period extended to 6 months. All of seroma needed no surgical interference and managed conservatively. Conclusion: The current study showed that both component separation and onlay mesh hernioplasty were safe and effective in the treatment of midline incisional hernias.