Abstract: This paper presented Several image processing methods for medical X-ray pictures: noise removal, contrast enhancement, and contour extraction. These methods, used to process X-ray pictures for mammary gland, kidney etc., obtain satisfactory experimental results, while the conventional processing methods are noneffective. Not only the view effect of pictures is improved, but also a lot of useful informations arc got, which are unable to get from normal X-ray pictures with eyes. They are valuble and important for improving clinical diagnosis results especially for that of early phymatosis.