The invention relates to Crystal form I and Crystal form II of dihydrochloride of N-(4-((3-chloro-4-fluorophenyl)amino)-7-((7-methyl-7-azaspiro[3.5]nonan-2-yl)methoxy)quinazoli n-6-yl)acrylamide represented by the following Formula (I), and preparation methods therefor, wherein the Crystal form I has an X-ray powder diffraction pattern having characteristic peaks at the 2 ? positions of 6.0?.2? 7.3?.2? 11.7?.2? 12.9?.2? 18.4?.2? 24.7?.2? and 26.3?.2? as determined by using Cu-K?radiation, and the Crystal form II has an X-ray powder diffraction pattern having characteristic peaks at the 2 ? positions of 5.0?.2? 7.0?.2? 10.1?.2? 17.0?.2? 26.0?.2? and 26.5?.2? as determined by using Cu-K?radiation.