Purpose: This study compares beneficiaries of Korean Medicaid with those under the National Health Insurance program, seeking to understand how each group utilizes their healthcare. Methods: Data were obtained from a Health Promotion Survey in 2005. Health status was measured by the respondents’ perception of health. Health service utilization included the availability of healthcare services, the type of healthcare institution, and intent to revisit. Predisposing and enabling factors, as well as health care needs were used for this study. Results: Compared to National Health Insurance beneficiaries, Medicaid beneficiaries reported lower levels of health status and fewer enabling factors. They had more chronic diseases and disabilities. Education level, existence of chronic diseases, exercise patterns, and disabilities were associated with health status. Conclusion: We found that Medicaid beneficiaries had fewer resources and higher levels of health needs. As Medicaid is reformed, policy makers and administrators should understand healthcare utilization behaviors of Medicaid beneficiaries and the factors hindering access to care.