Introduction: The RIPASA scoring system was established specifically for Asians. Chong CF in his study consisting of 312 patients who had an emergency appendectomy concluded that optimal cut-off threshold score for negative appendectomy was 7.5. Objective: To determine the diagnostic accuracy of RIPASA scoring system in presumptive accurate diagnosis of acute appendicitis by taking histopathology as the gold standard. Materials and methods: This Cross Sectional Study was carried out at Surgery department at a tertiary care hospital, Karachi over a period of 6 months, from 15th December 2019 to 15th June 2020. A total of 141 patients of both gender of suspected cases of acute appendicitis presenting with sign and symptoms were included in the study. Patients underwent detailed history, general and physical examination and scoring of patients according to RIPASA scoring scale and then decision of appendectomy was taken on the basis of RIPASA score. Removed appendix samples were sent for histopathology. Results: Age range in this study was from 15 to 50 years with mean age of 30.191±6.09 years and mean RIPASA score was 5.375±1.77. Majority of patients were males (58.9%). RIPASA score diagnosed 28(19.9%) and histopathology diagnosed 27(19.1%) patients with acute appendicitis. RIPASA score showed sensitivity of 85.2%, specificity 95.6%, diagnostic accuracy 94%, PPV 82.1% and NPV was 96.4%. Conclusion: We conclude that RIPASA scoring system is the scoring system of choice in diagnosis of the acute appendicitis with good sensitivity albeit a hit high and specificity albeit a bit low profile.