Objective: Gender differences exist in schizophrenia and bipolar disorder (BD), therefore the aim of the present study was to clarify the role of gender in cognitive deficits in these disorders. Methods: Cognitive performance was examined in schizophrenia (24M: 14F) and BD (16M: 24F) patients compared with age-, IQ- and gender-matched control participants (21M: 22F). The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to assess five cognitive domains: immediate memory/learning, visuospatial ability, language, attention, and delayed memory, which are summed to provide a Total score. Results: In comparison to controls, schizophrenia patients showed deficits on all domains, while BD patients had impaired immediate memory/learning, language and Total score. Schizophrenia patients showed deficits compared to BD in the Total score, immediate and delayed memory and visuospatial ability. The Total and domain scores were not different in men and women across or within groups. There were gender effects on four of the 12 individual cognitive tasks, in which female patients outperformed male patients. Further, there were gender differences across groups for three of the individual tasks: female schizophrenia patients showed poorer story memory and story recall compared to male schizophrenia patients; female BD patients had enhanced figure copy performance compared to male BD patients. Conclusions: The RBANS highlighted the cognitive deficits in schizophrenia and BD patients compared to controls and also each other. There were no overall gender differences in cognition.