The invention discloses equipment and a method for 3D printing of architectural ornaments. The equipment mainly comprises Y-axis guide rails, an X-axis guide rail, Z-axis guide rails, a movable forming platform, a wire feeder, a CMT power source system, a CMT sprayer, a water-cooling machine, a protective gas device, a central control system and the like, and the movable forming platform is arranged on the Z-axis guide rails. By means of connection, combination and control of the Z-axis guide rails, the Y-axis guide rails, the X-axis guide rail and other parts, accuracy in the Y direction, X direction and Z direction is achieved, objects in any shape can be rapidly formed, structures which cannot be obtained through traditional manufacturing methods can be perfectly printed, creativity of designers is freed, unrestrained imagination of the designers is met, and the aesthetic property and the grade of architectural ornament parts are improved. Compared with the mode adopting a laser, the CMT system is adopted by the equipment, the heat input amount is lower, a heat affected zone is smaller, deformation is smaller, the forming precision is higher, and the size error is smaller. Compared with traditional preparation processes for the architectural ornament parts, the cost is greatly reduced, and the precision is greatly improved.