<p>Marfan syndrome is an autosomal dominant multisystemic connective tissue disorder caused by mutations in the <i>FBN1</i> gene. Although clinical changes in the cardiovascular, ocular, and skeletal systems have been described in detail in Marfan syndrome patients, investigations about skeletal muscle alterations are still incipient. This systematic review describes cellular, molecular, and functional changes in skeletal muscles of patients and mice with Marfan syndrome. Study selection (from EMBASE, MEDLINE, and Web of Science databases), data extraction, and quality appraisal were performed by two independent reviewers. A total of 2634 articles were identified; 26 were included in the analysis based on the selection criteria. The risk of bias was evaluated using the Critical Appraisal Skills Programme and Joanna Briggs Institute Critical Appraisal tool for human studies and the Systematic Review Centre for Laboratory Animal Experimentation RoB tool for animal studies. The findings indicate that skeletal muscle alterations in Marfan syndrome are characterized by fibrosis, reduced muscle mass and myofiber size, compromised muscle regeneration, and impaired muscle function. Future studies are warranted to investigate the mechanisms involved in the development of this muscle phenotype to help develop effective strategies to improve skeletal muscle function and the quality of life of individuals with Marfan syndrome.</p>