The invention discloses a 3D (3-dimensional) molding machine, and belongs to the technical field of road construction machinery. The 3D molding machine comprises a crawler-type vehicle, a pouring device and a pavement molding roller, and is characterized in that a pouring cylinder and a high-frequency vibration instrument are controlled by a servomotor to move back and forth along a transversal groove through a gear and a rack, and the pouring cylinder is used for pouring in a thickening manner layer upon layer until a required thickness is detected by a road thickness control sensor; pouring cylinder automatically moves forwards to pour the next road according to the instruction of a road direction indicator, and when a section of the road is fully poured, the pavement molding roller starts to work, so as to enable the pavement to be molded through one step. According to the invention, the power required by the 3D molding machine is only one tenth of the combined-type machine for the large-scale road, or even less; the 3D molding machine has the advantages that the structure is simple and reasonable, the machine is economical and practical, the cost is low, the quality is good, and the effect is excellent, so that the 3D molding machine is suitable for paving small-scale roads.