Introduction: Acute appendicitis is the most frequent pathology in surgical emergency. The timeliness and effectiveness of the diagnosis is a parameter for evaluating the quality of care. Objective: To determine the concordance between clinical, surgical and pathological diagnoses in patients with acute appendicitis, “José Casimiro Ulloa” Emergency Hospital, Lima - Peru, 2018. Materials and methods: Observational, cross-sectional, retrospective, analytical study. Medical records of 222 patients diagnosed with acute appendicitis in 2018 were reviewed. Sample calculation with known population (1200), probability sampling. Patients> 18 years of age diagnosed with acute appendicitis, who had undergone surgery, had a pathological study, excluding pregnant women and patients with comorbidities. Data were processed and analyzed with SPSS v.25, descriptive statistics and kappa coefficien...