Currently, most 3D printers based on FDM can only use materials of one color, so there is a single color on printed papers.To solve this problem, on the basis of indepth research on how FDM 3D printer worked, a set of colorful 3D printer extrusion apparatus was designed, ordinary slice software was developed for the second time, colorful slice plugins were written, which matched the extrusion apparatus, and prototypes were trialproduced and debugged. By printing test, it is proved that the extrusion apparatus and color slice plugins meet the design requirements. Moreover, it provides reference for the further study of colorful 3D printing technology.