Abstract: Proposes a new method for the restoration of 3D image of wide-field microscope based on wavelet packet analysis denoising.Flexibility and the precise ability of local analysis in wavelet packet analysis during signal denoising are analyzed.The maximum-likelihood image-restoration algorithm(PML) is depicted as having super-resolution restoration ability.The wavelet packet is adopted to make denoising pretreatment first,and then the 3D image is restored by the PML algorithm.Experimental results show that the disturbance from the out-of-focus light in 3D microscopic images is greatly suppressed,noise effectively restrained,the definition and the SNR are obviously improved,and better effect of image restoration is obtained.