The invention discloses a methacrylate monomer used for preparing a coking inhibitor component. A preparation method of the methacrylate monomer comprises the following steps that firstly, normal C14-C22 alcohol and normal C4-C18 alkane with the terminal substituted with dichloro are used as raw materials, and chloroether with the total number of carbon of 18-40 is synthesized through the Williamson ether synthesis method; secondly, the chloroether is reacted with NH3 to synthesize primary amine; thirdly, the primary amine and methacrylic acid are subjected to condensation polymerization so asto synthesize N-methacrylamide, wherein the normal C14-C22 alcohol is 1-tetradecanol or 1-hexacosanol or 1-hydroxyoctadecane or 1-eicosanol or 1-docosanol, and the normal C4-C18 alkane is n-butane orn-pentane or n-hexane or n-heptane or n-octane or n-nonane or n-decane or n-hendecane or n-dodecane or n-tridecane or n-tetradecane or n-pentadecane or n-hexadecane or n-heptadecane or n-octadecane.The methacrylate monomer can be used for preparing the coking inhibitor component, the synthesis efficiency is high, and the cost is low.