To investigate the effects of gases as coolant and lubricant on machined surface, the micrograph and roughness value were obtained face to green cutting. Under the experiment conditions, water vapor and nitrogen gas may give a better restrain action to nubs adhibiting on the machined surface. And water vapor gave the lowest roughness value, while nitrogen gas has hardly help to lower roughness value. Other gases, only at a certain extent, can restrain nubs adhibiting and lower roughness value. Common characters of these gases are widely source, out of pollution, needless to disposing and so forth. With the view point of environment friendly, these gases may achieve green cutting.