Background: Diagnostic laparoscopy is often used when a patient is suspected of having acute appendicitis. The aim of this study was to assess the rate of other pathologies found during diagnostic laparoscopy for suspected acute appendicitis. Methods: This systematic search included studies with ≥100 patients who received laparoscopy for suspected acute appendicitis and reported on the histopathologic and other intra-abdominal findings. We performed a meta-analysis estimating the rate of other pathologies, and a sensitivity analysis excluding smaller cohorts (≤500 patients). Age groups, sex, specific findings, and geographic regions were investigated. Certainty of evidence was assessed with GRADE. Results: A total of 27 studies were included covering 25,547 patients and of these 793 had an unexpected pathology. The findings were benign pathology in the appendix (34%), malignancy (30%), gynecologic pathology (5%), gastrointestinal pathology (4%), or unspecified (27%). Meta-analysis showed an overall rate of unexpected findings of 3.5% (95% CI 2.7-4.3; moderate certainty), and the sensitivity analysis showed similar results. Malignancy found in the appendix when treating suspected acute appendicitis was 1.0% (95% CI 0.8-1.3%; high certainty). Conclusion: The rate of other histopathological findings in patients with suspected acute appendicitis was low and a malignancy in appendix was found in 1% of patients.