In order to evaluate the comfort degree of stereo video better,in this paper,the motion characteristics and three kinds of parallax of the object are put forward as the important factors affecting the stereo video comfort degree.Using these four factors obtained in different stereoscopic video content changes,an objecti ve evaluation of comfort standards in line is established with the human eye vie ws.Firstly,extract four influential factors of the stereo video comfort,including intra-frame′s para llax of significant objects,intra-frame′s parallax of related background,movement variables and the parallax between frames,then combine the theory of depth perception and lea st-square fitting method to establish an evaluation model,and finally use the subjective e valuation method to assess the model.Thus we obtain a method which can evaluate the comfo rt of stereo videos before these stereo videos are viewed.The evaluation results show that the model proposed in this paper can be a good simulation of t he human eye′s subjective feelings,and it is important for the study of stereo video comfort pe rception.