Despite the number of patients enrolled in ART is increased, HIV/AIDS continues to constitute a significant proportion of medical admissions and risk of mortality in low- and middle-income countries. As one of these countries, the case in Ethiopia is not different. The aim of this study was thus to assess reasons for hospitalization, discharge outcomes, and predictors of inpatient mortality among people living with HIV (PLWH) in Jimma University Specialized Hospital (JUSH), Jimma, Southwest Ethiopia. Prospective observational study was conducted in medical wards of JUSH from February 17th to August 17th, 2017. In this study, 101 PLWH admitted during the study period were included. To identify the predictors of mortality, multiple logistic regression analysis was employed. Of the 101 hospitalized PLWH, 62 (61.4%) of them were females and most of them (52.5%) were between 25 and 34 years of age. A majority (79.2%) of the study participants were known HIV patients, before their admission. Tuberculosis (24.8%), infections of the nervous system (18.8%), and pneumonia (9.9%) comprised more than half of the reasons for hospitalization. Moreover, drug-related toxicity was a reason for hospitalization of 6 (5.9%) patients. Outcomes of hospitalization indicated that the overall inpatient mortality was 18 (17.8%). The median CD4 cell counts for survivors and deceased patients were 202 cells/μL (IQR, 121–295 cells/μL) and 70 cells/μL (IQR, 42–100 cells/μL), respectively. Neurologic complications (AOR = 13.97; 95% CI: 2.32–84.17, P=0.004), CD4 count ≤ 100 cells/μl (AOR = 16.40; 95% CI: 2.88–93.42, P=0.002), and short hospital stay (AOR = 12.98, 95% CI: 2.13–78.97, P=0.005) were found to be significant predictors of inpatient mortality. In conclusion, opportunistic infections are the main reason of hospitalization in PLWH.