The Cooper test (CT) is used to assess cardiorespiratory fitness (CRF) in pre-adolescents and adolescents, although it was originally developed to assess healthy adults. The aim of this study is to examine the available scientific evidence on the reliability and criterion validity of CT when administered to pre-adolescents and adolescents. Systematic searches were performed in three electronic databases (MEDLINE/PubMed, SPORTDiscuss and Scopus). To examine reliability and validity, four separate meta-analyses were implemented, finding high heterogeneity in studies with low methodological quality. There was a paucity of research regarding absolute reliability, while studies attempting to develop or cross-validate VO 2max /VO 2peak equations were almost non-existent. Information on the psychometric properties of CT in pre-adolescents under 12 years of age is scarce. The findings of this review cast doubt on the usefulness of CT both in identifying CRF and in determining the impact of strategies developed to improve CRF among pre-adolescents and adolescents.