The miniaturization of many machine parts for machine tools is desired for the purpose of effectively utilizing space, energy saving and realizing desktop factories. To develop a compact and miniaturized NC machine tool, new downsized small parts such as electrical parts and mechanical parts must be developed. Therefore, in spite of the many requirements of the market related to the miniaturization of machine tools, a miniaturized machine tool has not been widely regarded. We have developed a new CNC lathe with a pipe frame structure. This structure is expected to enable the miniaturization of machine tools while sufficient space for the discharge of cutting chips and the wiring. The heat transfer between the pipe elements and connecting blocks strongly affects the axial displacement of the pipes. Therefore the heat transfer between the pipes can be reduced by controlling the temperature of the appropriate connecting blocks. Results for the thermal displacement control of this structure and the effects are reported in this paper.