Our aim was to investigate the association between self-rated health (SRH) and use of hospital services (ie, medical outpatient department, emergency department, and general ward. admissions). Cross-sectional study data were collected from 230 consecutive patients admitted to medical departments of a 2000-bed academic medical center in Taiwan using standardized operating procedures for data collection of SRH (ie, a single-item question inquiring overall perceived health status), medical disorders, depressive symptoms, and combined service utilization over a 1-year period (ie, number of visits to outpatient department, number of visits to emergency department, and number of hospitalizations). Electronic medical records were retrieved, with self-reported external medical visits added to in-hospital frequencies of service use to provide better estimation of health service utilization. Fifty-two percent of study patients rated their health as poor or very poor. Poor SRH was associated with more visits to medical outpatient department, emergency department, and hospital admission. Multivariate logistic regression demonstrated an independent association between poor SRH and services utilization after adjustment for age, gender, hypertension, diabetes, metastatic cancer, number of chronic illness, life-threatening event, life-time suicidal ideation, and depression. SRH may be a useful research tool to model medical service use for inpatients with chronic conditions.