The present invention provides a pyrimidine derivative and a use thereof. Thepyrimidinederivative is the compound shown in formula I or a pharmaceutically acceptablesalt, hydrate, solvate,metabolite or prodrug thereof, wherein, R1, R2, R3, R4 and R5 are, forexample, as defined in thespecification. The compound can act as an ALK inhibitor, and is for preparingan anti-tumormedicament for suppressing an anaplastic lymphoma kinase.(see formula I)
