To enhance CR image to improve its visual quality,an enhancement algorithm for CR image was proposed based on the multiresolution properties of wavelet analysis.The algorithm decomposes CR image into four sub-images,and uses different processing methods for the every sub-image enhancement.The sub-image with high frequency uses nonlinear function to enhance the detail definition,and then the unsharp masking(UM) method was used to enhance the sub-image with low frequency,at last gets the enhanced image by wavelet inverse transform.Experimental results demonstrate that the algorithm enhances CR image detail and the signal to noise ratio,the detail variance(DV) of the processed image is higher 3 times than the image enhanced by the general enhancement algorithms,and the value of DV/BV is higher 3.5 times than the other algorithms,while enhancing CR image with good visual effect.