To investigate the anatomical classification, diagnosis, indications, surgical methods, surgical techniques, intraoperative management, postoperative management and surgical efficacy of mitral valve malformation. Using the internationally used Delphi procedure, PubMed, Medline, The Cochrane Library, Wanfang and other databases were searched to review domestic and foreign literatures on congenital mitral valve deformity from January 1940 to February 2020, and select the ones of higher quality as evidence. In addition, with regard to the multiple disputes in the diagnosis and treatment of congenital mitral valve, experts from pediatric cardiac surgery and related disciplines have been convened for discussion for many times, and finally the following consensus has been formed to guide the clinical treatment and provide theoretical and technical guidance for the surgical treatment of congenital mitral valve malformation in China.