Executive functions (EF) play a fundamental role in the acquisition of learning, especially in mathematics. The literature seems to indicate that fitness and physical activity (PA) have an important impact on cognition, including EF. Although the relationship between these variables seems evident, few studies have investigated the mediation role of EF between fitness/PA and mathematical skills (MS). The purpose of this systematic review was analysing the relationship between EF, fitness/PA and mathematical skills (MS) in children aged 6 to 12 aged. The systematic review (CRD42021237840) used information from Pubmed, WOS and ERIC published between 2010 and 2021. Eligibility criteria were: scientific articles, in English, children aged 5-16 years, assessment of EF using standardised tests and inclusion of the three variables (fitness/PA, EF and MS). For assess risk of bias was used the Medical Education Research Study Quality Instrument (MERSQI). From the selected articles were extracted the following data: country, age, type of study, characteristics of the sample, evaluation instruments, physical activity program and results. From the 387 initial records, 21 studies with a total of 8601 participants have been selected to be included in the systematic review. Only one of the studies analysed shows a clear causal relationship between the three variables, while five show a linear relationship. EF could act as a mediator between fitness and MS but not between PA and MS, although long-term randomised and controlled intervention studies are needed. [Note: The issue number (62) shown in the footer on the PDF is incorrect. The correct issue number is 63.]