Background: Acute appendicitis is the sudden and severe inflammation of the appendix. Acute appendicitis isone of the most common acute abdominal emergencydisorders that often require emergencysurgical management in the hospital setting. It can be managed in a variety of clinical settings with both operative, and in many cases, using a non-operative approach. However, the surgical management sometimes ends with unfavorable outcomescharacterized by fatal and nonfatal postoperative complications.Despite its serious health complications, its magnitude and associated factors have been poorly explored in Ethiopia particularly in the selected study areas. Objective: Toassesstreatment outcome and associated factors of acute appendicitis inTibebeGhion Specialized Hospital(TGSH), Bahir Dar City, Northwest Ethiopia, 2022. Methods: Institution-based retrospective cross-sectional study among 671 acute appendicitis patient charts from January 1, 2019 January 1, 2022 at TGSH in Bahir Dar City. Systematic sampling technique was used to select patient charts. Data were collected by reviewing patient charts using pre-tested questionnaires. Data were entered into the Epi data version 3.1and exported to SPSS version 26 for further analyses. A binary logistic regression model was fitted to identify the associated factors. The odds ratio (OR) with a 95% confidence interval (CI) were used to measure the strength of association. Results:A total of 310 patients chart with a response rate of 100% were included. The mean age was 27.92±9.61 with a range of 15 to 71 years.Abdominal pain and anorexia were the main presenting complaint of patients with acute appendicitis. A bout 31(10.0%, 95% CI: 6.8-13.5%) patients unfavorable treatment outcome . Duration of illness >3days (AOR= 17.07, 95% CI: 2.13-136.94) and appendicial abscess (AOR=7.12, 95% CI: 1.79-28.39) were significantly associated with poor outcomes of appendicitis treatment. Conclusions:The outcome of appendicitis treatment was comparable to similar studies. Duration of illness, and intra operative findings were significantly associated with the outcome of acute appendicitis. Health care providers should immediately evaluate patients with abdominal pain for acute appendicitis and further validate it by using properinvestigations. Kay words: acute appendicitis, simple appendicitis, complicated appendicitis, outcome