The invention provides a halogenated dihydropyran pyrrolidone compound of formula (I) as shown in the description, or a crystal form of the compound, in the formula, X is fluorine, chlorine, bromine and iodine; L1 is vacant or vinyl; ring A is a naphthalene ring, a benzene ring or a thiophene ring; R1 is benzyl, alkyl of C1-C8 or (CH2)n-O-Bn; n is an integer of 1-5; R2 is benzyl, allyl or p-methoxybenzyl; and R3 and R4 are respectively independently selected from hydrogen, fluorine, chlorine, bromine, iodine, alkyl of C1-C3, nitryl or methoxyl. The invention further provides a preparation method of the compound or the crystal form thereof. The compound provided by the invention is simple and convenient in preparation method, gentle in reaction and high in yield, and in addition has certainanti-tumor activity and wide market application prospects.