The effect of color space conversion is directly related to the quality of digital printing. In response to the problem of large color difference in traditional color space conversion, a color space conversion method for digital printing using laser imaging radar technology is proposed. This method is divided into two parts. In the first part, the laser imaging radar technology is used to obtain the printed manuscript image and remove scattered point cloud data from the image using neighborhood averaging. In the second part, the RGB color space of the printed manuscript is converted to Lab space, and then converted to CMYK color space using a neural network model. A simulation test was conducted on this method, and the results showed that after applying the method proposed in this paper, the image color difference was between 0.22 and 0.37, the structural similarity index was between 0.88 and 0.95, and the conversion time was between 21.9 and 25.6 seconds. This indicates that the conversion effect of this method is better, and it can better ensure the consistency between the color and the original printing color after conversion, while improving conversion efficiency and reducing color deviation.