A new extrication algorithm for waist rail stripe center based on sequences images is proposed to accomplish structured-light stripe center extrication in rail wear dynamic measurement.The initial value of the stripe center,which is set to be the one in previous frame must be calibrated to offset deviation on y-axis caused by rail image vibration.Then,the approximate value of the stripe center is calculated by center of gravity method in normal direction.Structured light stripe center at sub-pixel precision is exacted though calculate signal-point Hessian matrix.The experimental results show that the proposed algorithm is fast,high precise,and can effectively resolve the problem of structured-light stripe center extrication in rail wear dynamic measurement.