The invention discloses an intelligent laser 3D printing device and method, and belongs to the technical fields of intelligent manufacturing and additive manufacturing. The intelligent laser 3D printing device comprises an outer shell, a semiconductor laser, a computer, a workpiece stage, a drive motor, a galvanometer X, a galvanometer Y, a scanning mirror X, a scanning mirror Y, a field lens, a molten pool and two CCD cameras; by utilization of a laser 3D imaging technology, 3D scanning imaging is performed on an entity object subjected to laser 3D printing, thereby achieving CAD modeling of the 3D entity object; and by utilization of a laser photoacoustic technology, internal defects of the entity object subjected to laser 3D printing are detected, thereby detecting the quality of the entity object subjected to laser 3D printing online in real time. According to the intelligent laser 3D printing method, the CAD modeling, rapid prototyping, and internal defect detecting functions of the entity object subjected to laser 3D printing are achieved by utilizing the same laser source, so that laser 3D printing equipment can be systematized and intelligentized. Therefore, the intelligent laser 3D printing device disclosed by the invention has the advantages of being convenient and rapid in printing, high in prototyping quality, high in intelligent degree, simple in structure, reliable in running, and the like.