Background: Chronic renal failure is on the rise to cause of morbidity and mortality worldwide. According to the latest world health organization data, renal disease deaths in Ethiopia accounted for 1.47% of total deaths. However, limited study had previously been conducted to show the magnitude of CRF among medical outpatients at St. Paulo’s hospital. Therefore, this study was designed to determine the magnitude of CRF and associated factors on medical outpatient’s patients.rnObjective: To assess the magnitude & associated factors of chronic renal failure from Medical outpatient department in St. Paulo’s Hospital, EthiopiarnMethod: This study used an institutional based cross sectional study. A trained nurse using structured questionnaire to interviewed participants. The survey questionnaire was first written in English and then translated into Amharic. 320 patients were interviewed from using a structured questioner and their Medical record revised. Data entry and analysis was done using SPSS statistical package version 20. The descriptive statistics was done. Logistic regression used to check for the presence of association between variables at the 95% confidence level.rnResult: The overall magnitude of CRF among medical outpatient department patients was 12.2%. CRF all age group likely develop the disease at statistically significant P value < 0.05. CRF cases with kidney infection were 5% greater than without kidney infection (AOR = 0.05, 95% CI 0.02, 0.16, P