The present invention provides a method for improving salt tolerance of a plant so as to enable the plant to be cultivated under a high salt concentration condition. The present invention discloses a method for improving salt tolerance of a plant, including suppressing or inhibiting a function of PERK13 (Proline-rich extensin-like receptor kinase 13) in a plant; the method for improving salt tolerance of a plant, wherein an antagonist of PERK13 is brought into contact with a root of the plant; the method for improving salt tolerance of a plant, wherein the antagonist is one or more species of microorganisms or a secretion therefrom; and the method for improving salt tolerance of a plant, wherein the suppression of the function of the PERK13 is carried out by suppressing expression of PERK13 gene, or the inhibition of the function of the PERK13 is carried out by inhibiting expression of PERK13 gene.
