Research has linked impaired insight in schizophrenia to poorer medication compliance and poorer treatment outcome. The current study attempts to replicate previous findings that impaired insight is related to deficits in work function. To examine this question, 121 participants with schizophrenia or schizoaffective disorder enrolled in vocational rehabilitation were classified as having unimpaired (N= 65), or impaired (N= 56) insight. Next, participants were assigned a work placement and their work performance assessed on the third, fifth, and seventh weeks of work by using the Work Behavior Inventory. Among the 85 participants who completed these weeks of work, a multivariate analysis of variance and subsequent analysis of variance showed participants with impaired insight had significantly poorer ratings of work quality, work habits, cooperativeness, and personal presentation. When measures of global intelligence and executive function were entered as covariates in individual analysis of covariance, groups differed on measures of cooperativeness and personal presentation. Implications for rehabilitation are discussed.