Disclosed are a xanthine derivative having the structure of the following general formula (I) or pharmaceutically acceptable salts thereof; further disclosed is a preparation method for the xanthine derivative or pharmaceutically acceptable salts thereof; and further disclosed is the use of the xanthine derivative or pharmaceutically acceptable salts thereof. Through experiments of influence of in-vitro DPP-IV activity inhibition experiments on glucose tolerance of normal mice and on blood glucose of mice with spontaneous diabetes, it proves that the compounds and pharmaceutically acceptable salts thereof show good DPP-IV inhibition activity, can be applied to prepare medicines in the medicines for treating dipeptidyl peptidase IV-related diseases, and more particularly, can be applied to the use of medicines for treating type II diabetes or diseases of abnormal glucose tolerance.