Purpose: Burst abdomen is a serious complication commonly observed after emergency midline laparotomy. Sarcopenia has been associated with increased morbidity and mortality after abdominal surgery. This single-center, retrospective, matched case–control study aimed to investigate the association between sarcopenia and burst abdomen in patients undergoing emergency midline laparotomy. Methods: Patients who had burst abdomen after emergency midline laparotomy were matched 1:4 with controls based on age and sex. Abdominal wall closure was standardized in the study period with the small bites, small stitches technique. CT assessed psoas cross-sectional area was used as a surrogate measure of sarcopenia. Sarcopenia was defined as the sex-specific lowest quartile of psoas cross-sectional area adjusted for body surface area. The primary outcome was the incidence rate of sarcopenia amongst cases and controls. Secondary outcomes were risk factors for burst abdomen and death that were identified using multivariate logistic regression analysis. Results: 67 cases were matched to 268 controls during May 2016–December 2019. BMI > 30 kg/m², liver cirrhosis, smoking, high ASA score and peritonitis were more frequently observed among cases. Multivariate analysis revealed that sarcopenia (odds ratio (OR) 2.3, p = 0.01), active smoking (OR 2.3, p = 0.006) and liver cirrhosis (OR 3.7, p = 0.042) were significantly associated with burst abdomen. ASA score ≥ 3 (OR 5.5, p = 0.001) and ongoing malignant disease (OR 3.2, p = 0.001) were significantly associated with increased 90-day mortality. Conclusion: Sarcopenia is associated with increased risk of burst abdomen after midline laparotomy. Prospective trials are needed.