The invention discloses a method for inducing meristematic nodules of a tree peony, comprising the following steps of: 1) inoculating a surface sterilized petiole onto a preinduction culture medium to carry out preinduction; and 2) transferring callus induced in the step 1) into an induction culture medium to induce the meristematic nodules. In the invention, an SH (Schenk and Hildebrandt) mediumis taken as a basic culture medium, a petiole thin layer culture method is adopted, the inductivity of the callus reaches up to 100%; and meanwhile, the meristematic nodules of the tree peony are initially induced, and the maximum inductivity reaches up to 85.7%. The propagation of the meristematic nodules of the tree peony is respectively realized on a solid culture medium and a liquid culture medium, and a new system of tree peony tissue in vitro propagation is provided.