The invention provides a novel preparation method of Apalutamide. According to the novel preparation method, 2-fluoro-4-bromo-N-methyl benzene methanamine amide, 1-amino cyclobutyl carboxylate hydrochloride, and the like are taken as initial raw materials, and substitution reaction is carried out so as to obtain 1-((3-fluoro-4-(methyl carbamyl)phenyl)amino) cyclobutane-1-carboxylic acid, wherein synthesis yield is higher than 70%, and purity is higher than 97.2%; then esterification is carried out so as to obtain 1-((3-fluoro-4-(methyl carbamyl)phenyl)amino) cyclobutane-1-carboxylic ester, wherein synthesis yield is higher than 83%, and purity is higher than 97.8%; and at last, ring closing reaction with 2-cyan-3-trifluoromethyl-5-isothiocyano pyridine is carried out so as to obtain Apalutamide, wherein yield is higher than 68%, and purity is higher than 98.1%. The preparation method possesses following advantages: the raw materials are easily available; technology is simple; operationis convenient; yield is high; and cost is low.