We develop a small NC milling machine based on the concept of a micro factory. We try to manufacture this machine for using even in the laboratory where there are lot of amateur machine operators for getting trial machine parts. The small NC milling machine size is about 150mm×100mm×270mm. It is about 1/10 of the general milling machines. To evaluate this machine's performances we first make square parts:5mm×5mm×2mm and we make sure that this square parts accuracy is kept within 0. 01mm. We also make one of typical machine parts : a gear, and a circular pyramidal shape which is called a 2. 5 dimensional sample.