OBJECTIVES:  Most people in Hong Kong are infected by varicella zoster virus (VZV) in childhood. The risk of herpes zoster (HZ) upon VZV reactivation increases with age. Lifetime risk of HZ is significantly age-related, affecting mainly those aged ≥50 years old, as a result of waned cell-mediated immunity. With an aging population in Hong Kong, it is anticipated that the HZ incidence will increase over time. We aimed to describe the patient characteristics, clinical and economic outcomes of hospitalized herpes zoster. METHODS:  A retrospective, observational study was conducted in a Hong Kong teaching hospital. Hospitalized patients aged ≥18 years with HZ as primary discharge diagnosis during year 2011-2012 (prior to zoster vaccine available in Hong Kong) were included. Treatment outcomes included HZ-related length of hospital stay (LOS), cost of treatment, and HZ-related complications. RESULTS: We reviewed 108 HZ cases (45.4% male and mean age 66±16 yeas) and 34 (31%) were immunocompromised patients. Median LOS was 6 days (IQR 3-9) days. HZ-associated complications occurred in 42 (38.9%) cases, with 16 cases (14.8%) of post-herpetic neuralgia. Median treatment cost was HKD29,094 (IQR HKD15,070-43,842) (USD1=HKD7.8). In multivariate analysis, underlying malignancy was associated with prolonged LOS (OR=6.05; 95% CI 1.22-30.02; p=0.028) and high treatment cost (OR=10.60; 95% CI 1.29-86.89; p=0.028). Immune diseases increased risk of HZ-associated complications (OR=3.55; 95%CI 1.20-10.50; p=0.022). In immunocompetent patients (n=74), age >70 years was associated with prolonged LOS (OR=3.25; 95% Cl 1.23-8.55; p=0.017) and high treatment cost (OR=3.47; 95% Cl 1.32-9.08; p=0.011). CONCLUSIONS: HZ-associated hospitalization, occurred most commonly in elderly, caused substantial economic burden and high complication rate. Underlying immune diseases were associated with increased risk of HZ-related complications in hospitalized HZ patients.