Objectives: To explore the factors of hospital utilization in senior veterans as a reference for medical policy to be used by the government. Methods: Using veteran population files and national health insurance inpatient claim data to analyze the factors associated with hospital utilization. A two-part model was used to examine the factors leading to hospitalization and the number of hospitalizations. Results: In 1999, the user rate was 24 per 100 veterans, and the discharge rate was 45 per 100 veterans. The regression results indicated that senior veterans who were male, unmarried, category 5 beneficiaries, having severe illness, lower educated, lower military rank, and living in nursing home, have a significantly higher rate and number of hospitalization. Conclusions: With the aging of senior veterans, the Department of Health and the Veterans Affairs Commission should reinforce the supply of medical services and long-term care for senior veterans.