The invention discloses a dragon-fruit grafting method. The dragon-fruit grafting method includes the following steps of (1) stock cultivating, wherein a cultivation-matured hylocereus or selenicereusvarietal plant is taken and serves as a stock, thorn bases on the stock are completely castrated off, and then cultivation is carried out; (2) stock treating, wherein a part of fleshy parts are cut on an edge which is a section of distance away from the top of the stock along the edge of a central vascular bundle, and a wedge-shaped or right-angle carved notch is formed; (3) scion treating, wherein a target-variety dragon-fruit branch is taken and cut into a single-thorn-base scion along the edge of the central vascular bundle; (4) grafting, wherein the single-thorn-base bud scion is put at the wedge-shaped or right-angle carved notch of the stock, jointing treatment and fixing are carried out, and an unhealed grafted seedling is obtained; (5) nursery stock healing cultivating. Accordingto the dragon-fruit nursery stocks grafted with the method, operation is easy, healing of a grafting opening is good, and the survival rate of the nursery stocks after grafting is 98% or above. The nursery stocks after grafting is standardized and coincident, a few bud-picking workers are wasted in cultivation and management after nursery stock planting, and the growth speed of the nursery stocksis higher.