PURPOSE: People with cancer experience significant physical and psychological symptoms, during as well as after primary treatment. Acceptance and Commitment Therapy (ACT), a psychological intervention, reduces both types of symptoms among individuals with chronic pain and emotional distress. Due to the unique challenges of cancer survivorship, this systematic review critically evaluates and synthesizes the literature on the context, mechanisms, and effect of ACT among adult cancer survivors. METHODS: Articles were retrieved from the CINAHL, MEDLINE via Ovid, Web of Science, PsycInfo, Scopus, Embase, Google Scholar, and Cochrane databases. Selected grey literature portals, clinical trial registries, and conference proceedings were also searched. The NIH tools were used to assess study quality and the revised Cochrane Risk-of-Bias tool to assess risk of bias RESULTS: Thirteen articles, reporting on 537 cancer survivors with various cancer types, were included. ACT significantly reduced anxiety, depression, and fear of cancer recurrence and improved psychological flexibility and quality of life. Outcomes such as pain and insomnia were understudied. Lack of participant blinding and non-random assignment were the most common methodological issues. A conceptual model is proposed that describes the possible influencing factors of an ACT-based intervention in cancer survivors. CONCLUSION: Review findings suggest that ACT is an effective intervention to improve some of the common concerns among cancer survivors. While all the studies in the review were recent (published 2015-2019), they examined only a limited number of outcomes. Hence, more methodologically rigorous studies which examine the effect of ACT on other troubling symptoms among cancer survivors are warranted. IMPLICATIONS FOR CANCER SURVIVORS: Incorporating ACT into comprehensive post-treatment survivorship care can enhance psychological flexibility and reduce anxiety, depression, and fear