The invention discloses a motion segmentation and three-dimensional (3D) expression method for a single view image sequence. The method comprises the following steps of: acquiring the single view image sequence, estimating the motion information and depth information of a main motion target by using a gradient descent method and evolving a break curve by using a level set method; verifying the estimated depth information and correcting unreliable depth information; minimizing an energy function by using the corrected depth information and the obtained break curve and estimating the motion information and depth information of the main motion target; and fixing the break curve, minimizing the energy function once again, verifying and correcting the reliability of the depth information and minimizing the energy function once again so as to obtain the depth information and motion information of every motion target. Motion segmentation and 3D expression can be performed at the same time and the number of targets in the image sequence does not need to be known in advance. The method has wide applicability.