The present invention discloses rice serine hydroxymethyltransferase coded gene OsSHM4 mutants and application thereof. The rice serine hydroxymethyltransferase coded gene mutants are obtained in a manner that T at a 461st position of a CDS sequence region of a wild type rice OsSHM4 gene is mutated to C, so that coded amino acids thereof are mutated from leucine to proline. A CDS sequence of the wild type rice OsSHM4 gene is shown in SEQ ID NO. 1. After mutation of serine hydroxymethyltransferase coded genes OsSHM4, under a field experiment condition, S and Se content of rice shoots is remarkably improved without influencing biomass of rice. After wild type serine hydroxymethyltransferase coded genes OsSHM4 are genetically modified to complement the mutants, S and Se content of shoots of complemented strains is restored to that of wild type rice water planting.