This study examined signs of mania on the Rorschach, specifically whether manic inpatients (n = 24) produce different thematic content and thought disorder than comparison groups of paranoid schizophrenic (n = 27) and schizoaffective (n = 25) inpatients. Rorschach protocols were scored by a trained rater for the Thought Disorder Index and the Schizoid-Affective Rating Scale. Results indicated that all 3 groups had moderate levels of thought disorder, but the manic inpatients produced significantly more combinatory thinking and affective content responses than the other 2 groups. The paranoid schizophrenic and schizoaffective patients did not produce significantly more schizoid content and were not different on any other types of thought disorder than the manic patients. These findings are discussed in terms of the contribution of thought disorder and affective thematic content in making the diagnosis of mania on the Rorschach.