The invention discloses a molecular marker, SAV1 (Salvador family WW domain-containing protein 1) gene, for early diagnostics of hysteromyoma and an expression product thereof. By using QPCR (quantitative polymerase chain reaction) and Western blot methods, it is proved that the SAV1 gene has differential expression in hysteromyoma tissues and normal tissues and can be used as an index for the early diagnostics of hysteromyoma. In addition, the invention also discloses the SAV1 gene and the expression product thereof which may be used as targets for treating hysteromyoma and used for guiding the development of new drugs.