Background: Cohorts describing cause specific mortality in HIV-infected patients initiating antiretroviral therapy (ART) operate on an outpatient basis. Hospitalized patients represent the spectrum and burden of severe morbidity and mortality in patients on ART. Objective: To determine the causes and outcomes of hospitalization among adults receiving ART. Methods: A prospective cohort study. We enrolled 201 participants (50% female) with median (IQR) age and CD4 count of 34 (28-40) years and 91(29-211) cells/uL respectively. Results: The most frequent causes of hospitalization were tuberculosis (TB) (37, 18%), cryptococcal meningitis (22, 11%), zidovudine (AZT) - associated anemia (19, 10%), sepsis (10, 5%) and Kaposi’s sarcoma (10, 5%). Forty two patients (21%) died: 10 (24%) had TB, 8 (19%) had cryptococcal meningitis and 5 (12%) had sepsis, 9 (21%) had undiagnosed neurological syndromes while 10 (24%) had other illnesses. Predictors of death included low Karnofsky performance score of < 40 (OR, 21.1; CI 1.43- 31.6) and age >34 years (OR, 7.65; CI 1.09- 53.8). Conclusions: Opportunistic infections, malignancy and AZT-associated anemia contributed to most hospitalizations and mortality. It is important to intensify prevention, screening, and treatment for these opportunistic diseases and early ART initiation in HIV-infected patients. Tenofovir-based regimens, unless contraindicated should be scaled up to replace AZTbased regimens as first line ART drugs.