Due to the problem of the knowledge of noise using wavelet transform denoising,a new method based on orthogonal wavelet transform using block-based singular value decomposition for infrared image denoising is proposed.Firstly,infrared image is decomposited using orthogonal wavelet transform.For the high frequency components of image decomposition,the wavelet coefficients are estimated using improved block-based singular value decomposition.And the singular vectors are modified using fourier transform.Then the high frequency coefficients of signal was obtained.The denoised image is obtained through inverse wavalet transform by the low frequency image and the high frequency images.The experimental results show that the infrared image can be denoised effectively in this means without the knowledge of noise.The SNRs are improved substantially,and the visual quality is achieved well.