Purpose: This study investigated the long-term development of incisional hernia after implementation of a standardized surgical treatment strategy for burst abdomen in abdominal midline incisions with a continuous mass closure technique. Methods: The study was a single-center, observational study evaluating all patients treated for burst abdomen between June 2014 and April 2019 with a long-term follow-up in October 2020. In June 2014, a standardized surgical treatment for burst abdomen involving a monofilament, slowly absorbable suture in a continuous mass-closure stitch with large bites of 3 cm and small steps of 5 mm was introduced. The occurrence of incisional hernia was investigated and defined as a radiological-, clinical-, or intraoperative finding of a hernia in the abdominal midline incision at follow-up. Results: Ninety-four patients suffered from burst abdomen during the study period. Eighty patients were eligible for follow-up. The index surgery prior to burst abdomen was an emergency laparotomy in 78% (62/80) of the patients. Nineteen patients died within the first 30 postoperative days and 61 patients were available for further analysis. The long-term incisional hernia rate was 33% (20/61) with a median follow-up of 17 months (min 4, max 67 months). Conclusion: Standardized surgery for burst abdomen with a mass-closure technique using slow absorbable running suture results in high rates of long-term incisional hernias, comparable to the hernia rates reported in the literature among this group of patients.