The invention provides a three-dimensional curve perfect diffusion solar simulator. A D50 linear tube is taken as a standard linear light source (1); a curve diffuse reflection device (3) and a curve specular reflection device (2) are arranged along an axis of the linear light source; a diffuse transmission curve element (4) is arranged on a light path; and the uniformity of light of a plane where an irradiated object is positioned meets the requirement through multiple times of internal reflection and transmission of the light so as to improve optical spectrum performance. The three-dimensional curve perfect diffusion solar simulator has the basic integrating sphere function, meets the requirement of large area diffuse reflection illumination, has low manufacturing difficulty, solves the problems of the uniformity of the light and spectrum fitting and matching, and meets the requirement of three-dimensional printing, grating manufacturers and holographic paper manufacturing enterprises on the special illumination condition.