Back ground: Depression is a mental disorder that persuasive in the world and affects us all. Itrnaffects up to 50.6% in medical settings out patients in Ethiopia. While the disorder can bernreliably diagnosed and treated in primary care, it’s unrecognized and under managed (0 %rndetection rate in some medical settings).rnObjective: To assess the prevalence and associated factors ofrndepressions among adult inrnpatients in medical and surgical outpatient departments in Dessie referral hospital, north eastern,rnEthiopia, 2017rnMethods: An institution based cross-sectional study was conducted from 10-15 March 2017 atrnDessie referral hospital and comprised patients in the Medical and Surgical outpatientrndepartments at the time. The sample size was determined using a single population proportionrnformula. Participants were selected using systematic random sampling techniques. The calculaternsample size was 424 adult patients. The prevalence of depression was assessed using PatientrnHealth Qurstionnaire-9. Descriptive statics, bivariate and multivariate were performed usingrnSPSS 20.rnResults: Among the 414 study participants, 214(51.7%) were males. The mean age of thernrespondents was 39.01 (SD± 16) years. In this study, female were 2 times more likely tornexperience depression compared with male P=0.012 [AOR=1.926, 95% CI: 1.152, 3.221)] andrnParticipants who were divorced and widowed were 3 times more likely to have depression asrncompared with participants who were married P = 0.03[AOR=3.076, 95% CI: 1.114,8.490)].rnConclusion and recommendation: The prevalence of depression among patients in medical andrnsurgical OPDs in Dessie referral hospital was relatively high (39.1%). Depression hadrnstatistically significant association with age, sex, marital status, occupational status, chronicrnillness, substance use and family history of mental illness. The major implication of these studyrnfindings on the health system is the importance of ensuring support to primary health carernservices for early detection and referral of depression.rnKey words: Depression; Prevalence; Associated factors; Medical and Surgical out patients.