The present invention relates to a pyrimidine derivative, a method for preparing same and use thereof in medicine. In particular, the present invention relates to a pyrimidine derivative represented by general formula (I), a method for preparing same and a pharmaceutically acceptable salt thereof as well as use thereof as a therapeutic agent, in particular as a FGFR4 kinase inhibitor, definitions of each substituent in the general formula (I) being the same as those defined in the description.本發明涉及嘧啶類衍生物及其製備方法和醫藥用途。具體而言，本發明涉及一種通式（I）所示的嘧啶類衍生物、其製備方法及其可藥用的鹽，以及它們作為治療劑，特別是作為FGFR4激酶抑制劑的用途，其中通式（I）中的各取代基的定義與說明書中的定義相同。
