Background <p>We aimed to systematically assess the measurement properties of ageism scales tested in a population of health care professionals and students.</p> Methods <p>Eligible studies were peer-reviewed English language publications that sampled a population of health care professionals and/or students and focused on developing and/or evaluating at least one psychometric property of an ageism scale. A systematic review was conducted until 15th December 2023 via the following databases: PubMed, Embase, PsycInfo, and Scopus. Data extraction and quality assessment (including a risk of bias evaluation) of the included studies was undertaken by two reviewers in accordance with COSMIN guidelines.</p> Results <p>Out of 1,626 articles selected, 51 were eligible for inclusion reporting evidence on the measurement properties and/or on the development of eight ageism scales. Only five scales have been specifically developed for health care professionals or students. Furthermore, the available scales fail to cover all dimensions of ageism, with many focusing solely on stereotypes and the explicit and negative dimensions of ageism and less on the implicit dimension. Our review also revealed that the evidence was often of poor quality and limited to only a few psychometric properties. Finally, we found that the assessed scales had poor theoretical foundations.</p> Conclusions <p>This study emphasises the need to develop and validate a comprehensive scale that measures the complexity of ageism in the health care sector.</p> Trial registration <p>PROSPERO registration CRD42021276470. </p>