The invention discloses a curve tortuosity description method based on a curved hierarchy tree, relating to the geographic information scientific field, and comprises the steps of performing geographical curve synthesis based on conglutination transformation to obtain a curved polygon of a curve, determining the home of the curved polygon through overlay analysis, establishing the hierarchy tree corresponding to each curving under a largest dimension, and establishing the curved hierarchy tree of a whole curve. The method identifies curved units of different dimensions through controlling conglutination transformation widths, and establishes a curved hierarchy tree, curving expresses tree nodes, and a hierarchical structure expresses the topological structures of curved units of different dimensions. The method displays curve partial and whole tortuosity in a comparatively complete way, meanwhile more comprehensively considers the nested relation among different curved hierarchies, overcomes defects of the prior art, better describes curve tortuosity, comprehensively reflects curve forms and structure characteristics, and is of great importance in geographical characteristic research.