An image fusion algorithm using pseudo-Wigner Ville distribution (PWVD) is proposed.Firstly,a 1-D pseudo Wigner Ville distribution fuction is applied to nonoverlapping N-pixel window slices of the original image in different orientations,the resultant data is arranged as N energy maps according to the orientation where the mean square root is max. Then,the fusion principle of multiscale decomposition of the source images is the max partial energy of energy map in high frequency and the max variance of energy maps in low frequency. So,the resultant data can be arranged as N energy maps in different frequencies. Finally,the fused image is formed through contrary PWVD to the fused energy maps. The fusion experiment for infrared and visible images,multifocus images,computer X-ray tomography and magnetic resonance images,infrared and synthetic aperture radar images are taken,and the entropy comparison between fused image and source images is given. The results show that the fused image obtained by the presented algorithm preserves the abundant information of the source image.