Cross-correlation methods have been applied to the measurement of bubble film parameters in ship wake from a new aspect.The high-speed CCD camera is used to acquire the images of simulating ship wake images,and the velocity of micro-bubble in the ship wake is computed from image posttreament.Through improving cross-correlation algorithm commonly used for analysis of flow field,the fast Fourier transform(FFT) has been used to fastly compute the cross-correlation function.The selection of sizing grid for computing cross-correlation is discussed,and curved surface fitting is applied to improve the computing level for the location of max value of cross-correlation function,and the motion direction of micro-bubble in ship wake flow with sub-pixel level is obtained.