Herpes zoster results from the reactivation of the varicella-zoster virus. Pain is the most common manifestation of the disease and has a substantial impact on health-related quality of life. Acute pain and its correlated risk factors have been less investigated in previous studies. This study was designed to evaluate the relationships between acute pain severity and some demographic and clinical features of the patients. Two hundred twenty-three adult patients with a diagnosis of herpes zoster were enrolled. Herpes zoster was diagnosed by a dermatologist and an infectious diseases specialist. Severity of acute pain was measured using the visual analog scale. Data about the medical and demographic characteristics of participants were collected. The mean (±SD) severity of acute pain in patients was 56.8 (±24.6). Acute pain severity was significantly associated with age (p = .045), female gender (p = .048), smoking (p = .021), immunosuppression (p = .022), and presence (p = .001) and duration (p = .028) of prodromal phase. Body mass index, diabetes mellitus, and location of dermatomes did not correlate with the intensity of pain. This study suggests that age, gender, cigarette smoking, immunosuppressed state, and presence and duration of prodromal phase are the major correlates of acute pain intensity in herpes zoster.