Psychosocially vulnerable prisoners under stressful conditions of confinement are ill prepared to cope and at risk for developing suicide intention. The present study examined the relationships of depression, hopelessness, reasons for living, mental health problem history, suicide attempt lethality history, and stressful segregation housing with suicide ideation in 134 prisoners. Prisoners housed in segregation were found to have significantly higher levels of depression and suicide ideation than prisoners in general population. A hierarchical regression model of suicide ideation found significant interactions between mental health problem history, suicide attempt lethality history, and hopelessness with anticipated segregation stress, independent of depressed mood. Results of the study are discussed in terms of the stress-vulnerability model, various methodological limitations, and future research.