A method for hydroponically cultivating a plant to enable long-term cultivation of the plant in a high salt concentration environment is provided. It has a cultivation process of hydroponically cultivating a plant body with a cultivation solution having a sodium chloride concentration of 1% by mass or more, and at least a part of the root of the plant body once or twice in the middle of the cultivation process A hydroponic cultivation method of a plant in a high salt environment, wherein the salt tolerance of the plant body is maintained by performing a salt tolerance imparting treatment in which a salt tolerance imparting agent is contacted with the plant.高塩濃度環境下での植物体の長期間栽培を可能とするための、植物体の水耕栽培方法を提供する。植物体を、塩化ナトリウム濃度が１質量％以上である栽培用溶液で水耕栽培する栽培工程を有し、前記栽培工程の途中で１回又は２回以上、前記植物体の根の少なくとも一部に耐塩付与剤を接触させる耐塩性付与処理を行うことによって前記植物体の耐塩性を維持する、高塩環境下における植物の水耕栽培方法。
