Laser active illumination imaging has the advantages of long range, high resolution, obtaining the target image in complex environment such as low illumination background. However, the image is disturbed by speckle noise. Gaussian filtering, mean filtering and adaptive filtering methods are applied to the simulation experiment respectively for speckle noise suppression. Experiments show that compared with Gauss filtering and mean filtering, the adaptive filtering can effectively suppress image noise and keep edge and detail information of the image. Speckle suppression experiment for the obtained single frame and multi-frame cumulative average laser active detection image is carried out by using the adaptive filtering method. Quantitative analysis is carried out with speckle contrast ratio. Results show that the cumulative mean of multi-frame short exposure images can effectively suppress the image speckle noise. Adaptive filtering can further reduce the image speckle noise.