This study examined whether depression mediated the relationship between perceived health status and suicidal ideation among elderly male prisoners in South Korea. Male inmates aged 50 years or older in the correctional facilities were surveyed in December 2020; 141 male participants were included in the statistical analysis. The hierarchical regression results showed that suicidal ideation increased with poorer perceived health among elderly male inmates. Further, perceived health status negatively affected depression, while depression positively affected suicidal ideation. Depression had a significant partial mediating effect between perceived health and suicidal ideation. First-time offenders were more vulnerable to suicide risk than repeat offenders. These findings highlight the need for treatment programs and cognitive-behavioral models to identify inmates' psychosocial risk factors, and assess their mental health. Additionally, correctional facility staff should be educated in suicide prevention, and systematic crisis intervention programs should be provided for those who attempt suicide. This study contributes consideration of the Korean context to the literature on the association among perceived health status, depression, and suicidal ideation in elderly male inmates.