To enhance accuracy of the size and the shape of manufactures, and to shorten the time of operation, there is provided a method for manufacturing a 3D model comprising steps of designing the 3D model and collecting shape data of the 3D model slicing the 3D model into several layers in height, dividing each of the layers into several sublayers so that a sublayer is formed by depositing a material at once, depositing a material in accordance with shape data in relation to a sublayer divided from one layer of the 3D model, and deciding whether the one layer of the 3D model has been completed. The method is conducted using computer-aided design and computer aided manufacturing system including a variable deposition manufacturing apparatus. The apparatus comprises a material feeder 11, an electrical melting device 13 connected to the material feeder 11 through a conduit 12, a variable nozzle 15 connected to the variable nozzle 15 through a flow controller 14, a three-dimensional moving mechanism for moving the variable nozzle is in relation to the 3D model and a turntable adapted for rotating the 3D model.