INTRODUCTION: COVID-19 is an infectious disease that causes severe acute respiratory syndrome. A large variety of exercise capacity tests are used for the evaluation of post-COVID-19 patients, but the psychometric properties of these exercise tests remain undetermined in this population. This study aims to critically appraise, compare and summarise the psychometric properties (validity, reliability and responsiveness) of all physical performance tests that are used to assess exercise capacity in post-COVID-19 patients. METHODS AND ANALYSIS: This systematic review protocol follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will include studies with hospitalised adult post-COVID-19 patients (aged 18 years or older and with a confirmed diagnosis of COVID-19). The research will cover randomised controlled trials (RCTs), quasi-RCTs and observational studies published in English and performed in the following settings: hospital, rehabilitation centre, outpatient clinic. We will search the following databases with no date restrictions: PubMed/MEDLINE, EMBASE, SciELO, Cochrane Library, CINAHL and Web of Science. Two authors will independently assess the risk of bias (using the Consensus-Based Standards for the Selection of Health Measurement Instruments Risk of bias checklist) and the certainty of evidence (using the Grading of Recommendations, Assessment, Development and Evaluations). According to the results obtained, data will be meta-analysed or reported narratively. ETHICS AND DISSEMINATION: No ethical approval is required for this publication since it will be based on published data. Results of this review will be disseminated via peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42021242334.