The conditions of incarceration and the sociodemographic and health characteristics of 95 older male inmates of a federal correctional facility were studied to determine the relationship of such variables to rates of psychiatric disorder among older male inmates. A total of 51 inmates (53.7 percent) met one-month criteria for psychiatric disorder, a much higher rate than among a community sample of men in the same geographic area. Compared with inmates without such disorders, inmates with disorders were likely to be younger, to have a history of psychiatric disorder and substance abuse, to have poorer physical health, to have impaired social support, and to be serving a determinate sentence with no possibility of parole. Few were receiving treatment while incarcerated.