The concept of mizaj corresponds to the idea of personalized medicine and is the main diagnostic principle of Persian medicine (PM). This study aims to investigate diagnostic tools for the detection of mizaj in PM. In this systematic review of articles published before September 2022, articles were searched for in the Web of Science, PubMed, Scopus, Google Scholar, SID databases, and gray literature. The titles of the articles were screened by researchers and relevant articles were selected. Abstracts were reviewed by two reviewers to select final articles. Subsequently, the articles found were critically evaluated by two reviewers according to the CEBM method. Finally, article data were extracted. Of the 1812 articles found, 54 were included in the final evaluation. Of these, 47 articles were related to the diagnosis of whole body mizaj (WBM). WBM was diagnosed in 37 studies using questionnaires and 10 using expert panels. In addition, six articles examined the mizaj of organs. Only four of these questionnaires were found with reported reliability and validity. There were two questionnaires for assessing WBM, but neither had sufficient reliability and validity. Questionnaires that assess organs had weak designs and lacked sufficient reliability and validity.