Background: Psychological distress is associated with worsening symptoms during the active treatment period and lower quality of life in women with early-stage breast cancer. Many studies have indicated risk for heightened psychological distress across the breast cancer trajectory. Aim: The purpose of this review is to examine the literature for instruments used to measure psychological distress among women with breast cancer during chemotherapy. Methods: This study used the Arksey and O’Malley framework of scoping reviews. Two databases, PubMed & CINAHL, were searched for peer-reviewed original articles that were published within the last ten years, included participants with a diagnosis of breast cancer stages I to III, and receiving chemotherapy, English text articles, and studies that report psychological distress measures.  Results: The initial screening yielded 529 relevant studies. After applying the exclusion criteria, a total of 17 studies concerning the assessment of psychological distress during chemotherapy were retained for the analysis of variables and measures of psychological distress. The instruments used to measure for psychological distress varied with a total of 22 measures. The most frequently utilized measure was the Hospital Anxiety and Depression Scale ( n=5), followed by the Impact of Event Scale ( n=2), the Distress Thermometer ( n=2), and the Perceived Stress Scale ( n=2).  Conclusion: This review identified the gaps related to inconsistencies in the operationalization and instruments used to measure psychological distress among breast cancer survivors during chemotherapy. Standardization of measures assessing psychological distress, along with conceptual clarity, is essential for measuring distress in research and clinical practice.