Background: Individuals experiencing psychosis can present with elevated levels of depression and anxiety. Research suggests that aspects of depression and anxiety may serve an avoidant function by limiting the processing of more distressing material. Acceptance and Commitment Therapy suggests that avoidance of aversive mental experiences contributes to psychological inflexibility. Depression and anxiety occurring in the context of psychosis have a limiting effect on quality of life. No research to date has investigated how levels of psychological flexibility and mindfulness are associated with depression and anxiety occurring following psychosis. Aims: This study investigated associations psychological flexibility and mindfulness had with depression and anxiety following psychosis. Method: Thirty participants with psychosis were recruited by consecutive referral on the basis that they were experiencing emotional dysfunction following psychosis. The Hospital Anxiety and Depression Scale (HADS), Positive and Negative Syndrome Scale (PANSS), Acceptance and Action Questionnaire (AAQ-II) and the Kentucky Inventory of Mindfulness Skills (KIMS) were used. A cross-sectional correlational design was used. Results: The depression and anxiety subscales of the HADS both had significant correlations with psychological flexibility (as assessed by the AAQ-II) and aspects of mindfulness (as assessed by the KIMS). Hierarchical regression analyses indicated that psychological flexibility, but not mindfulness, contributed significantly to models predicting 46% of variance in both depression and anxiety scores. Conclusions: Although aspects of mindfulness are associated with depression and anxiety following an episode of psychosis, psychological flexibility appears to account for a larger proportion of variance in depression and anxiety scores in this population.