The invention discloses an enhancement method for a naked eye 3D image and relates to the technical field of 3D display. First, spatial domain enhancement based on Contourlet is utilized for adjusting the proportion of a low-pass image and the proportion of a detail image in the original image, the component which the detail image accounts for is enlarged, and the contrast ratio of the image can be increased through linear stretch; through a non-linear gain function, the band-pass directional sub-band coefficient containing speckle noise is adjusted, so that the purposes of enhancing detail and removing noise are achieved; a quantitative comprehensive evaluation function is utilized for better considering three indexes of a contrast ratio, definition and a signal-to-noise ratio. By the utilization of the enhancement method for the naked eye 3D image, the definition of an object is increased, the overall noise of the image is lowered, the quantitative performance indexes are comprehensively improved, and the overall vision effect is better.