This application relates to an automatic mold changing table for 3D molding, comprising a three-layer mounting frame including a top plate, a middle plate, a bottom plate, and connecting columns. The top plate, middle plate, and bottom plate are sequentially fixedly connected by the connecting columns. The mold changing device includes a mold body, a worktable, and a drive mechanism. Multiple mold bodies are provided, one of which is a working mold, and the others are replacement molds. A lifting slot is provided in the center of one side of the top surface of the middle plate. The worktable is located at the lifting slot and is lifted. A square protrusion is fixedly provided in the center of the top surface of the middle plate, and strip-shaped barriers are fixedly provided around the perimeter of the top surface of the middle plate, forming a U-shaped groove between the strip-shaped barriers and the square protrusion. The drive mechanism includes a lifting component and a sliding component. The lifting component drives the lifting of the upper and lower working molds, and the sliding component drives the mold body within the U-shaped groove to move along the U-shaped path of the groove. This application has the advantages of facilitating mold changing and improving mold changing efficiency.