Individuals with psychotic disorders are at increased risk for suicidality. Demographic and clinical characteristics were compared in individuals with psychotic disorders reporting either high or low suicidality. Among this sample of 259 partial hospital patients, 116 (44.8%) were classified as high risk on the suicidality section of the Mini Neuropsychiatric Interview, and 143 (55.2%) were considered low risk. Bivariate analyses revealed that patients classified as high risk demonstrated greater depression severity, more relationship difficulties, greater emotional lability, and more substance use problems. A logistic regression model indicated that substance use was the most powerful predictor of higher levels of suicidality. Monitoring and intervention for substance use should be targeted as a particularly important aspect of treatment for acutely ill patients diagnosed with psychotic disorders.