A system of rapid prototyping, comprises a calculate controller, a stage, a deliver, a frame former, a filler and a forming machine. A board material was disposed on the stage by the deliver. The frame former heats up the board material to melt the board material and then forms at least a space on the board material. The filler fills a solidable liquid into the space. The deliver disposes another board material on the board material filled with solidable liquid and repeats the abovementioned steps until the plurality of spaces constitute the target article. And then the forming machine heats up the board materials to melt the board materials, meanwhile, the solidable liquid is solidified to form the target article. Wherein the calculate controller connects and operates the deliver, the frame former, the filler and the forming machine.