The present invention discloses a halftone processing of image and text auto detection, which is used to keep both the bit depth of images and the clarity of text when faxing or copying documents. The process of the present invention is stated as follows: choose the background color from the master copy, separate the content of the master copy into images and text with the chosen background color as the criterion, process the images with halftone processing, process the text with line art processing, and then output the processed images and processed text as a whole.