The authors examined the prevalence and predictors of sexual dysfunction in a sample of 3,717 psychiatric inpatients assessed with the Minimum Data Set-Mental Health Version 1 (MDS-MH 1.0). Sexual dysfunction was found to be less prevalent in inpatient psychiatry (17%) than is typically reported in community settings. Severe depression symptoms, use of antidepressants, and cardiopulmonary conditions emerged as powerful predictors of sexual dysfunction. More research is needed on the assessment and treatment of sexual dysfunction in psychiatric inpatients, particularly focusing on attitudes of assessors, patients, and interactions between medical, psychiatric, and medication characteristics.