The invention belongs to the technical field of mold printing based on the 3D technique, and particularly relates to a method for printing the top of a hollowed-out mold through the FDM technique. The method for printing the top of the hollowed-out mold through the FDM technique comprises the following steps of (1) designing, specifically, the mold is divided into a frame structure for designing, the mold comprises a top sealing cover plate, an upper printed mold body and a lower printed mold body, and a bevel-angle supporting table is designed under the top structure of the lower printed mold body; and (2) printing, specifically, the top sealing cover plate and the lower printed mold body are printed through the FDM technique according to a mathematical model, a printing program is stopped, the top sealing cover plate is placed on the bevel-angle supporting table of the lower printed mold body, and finally, the upper printed mold body continues to be printed based on the lower printed mold body through the printing program till the whole printing process is completed. According to the method, the mold frame structure is printed through the FDM technique, the top sealing cover plate is printed independently, the top of the mold is printed by means of the top sealing cover plate, the defect that a hollowed-out structure cannot be printed through the FDM technique is overcome, and the FDM mold is more environmentally friendly and efficient.