Purpose: This is a systematic review of the usefulness of the MacArthur Competence Assessment Tools (MacCAT) in assessing the decision-making competence in patients with depression. Design and Methods: A systematic literature search was performed. Findings: Eleven studies met the search criteria. The decision-making capacity was impaired in 9–31% of the patients with depression. There was inconsistency regarding the differences of MacCAT scores between patients with depression and controls, while relatively large effect sizes were found on the Appreciation and Reasoning MacCAT subscales. Practice Implications: The MacCAT appears to be a useful tool for measuring decision-making capacity in patients with depression, but the association between depression and competence is not consistent. The mechanisms mediating such association are likely to be complex and multifactorial.