As the time-frequency characteristic of single wavelet base is difficult to match with complex image feature,the image denoising effect could hardly be improved further in the wavelet threshold denoising method.A new image denoising method based on linear combined wavelet base is proposed.Firstly,a new wavelet base is constructed by linear combination with multiple differences orthogonal wavelet base,and then the combined wavelet base is used to decompose the image.Finally the denoising image is obtained by threshold processing.The combined wavelet base can match well the image feature with adjusting combined coefficients to further enhance the image denoising effect.The experimental results indicate that the denoising effect of the method is superior to the single wavelet base method with 3.5 dB improvement of Peak Signal-to-noise Ratio(PSNR) at most.