The invention relates to a new monofunctional acrylamide compound with a capsaicinoid functional structure and a preparation method and application thereof. The acrylamide compound has the chemical structural formula (I) in the specification, wherein in the formula, R1, R2, R3 or R4 represents alkyl, OH group, OCH3 and other substituent groups. The monofunctional acrylamide compound with the capsaicinoid functional structure contains not only a capsaicin important active group, but also active double-bonds capable of performing polymerization reaction, the synthesis method is simple and easy to operate, the yield is high, and the monofunctional acrylamide compound can make up for the defect that the mass production of natural capsaicin is limited by complicated extraction processes and the output of hot pepper and simultaneously make up for the insufficiency that the natural capsaicin can only be used as a pure additive. The monofunctional acrylamide compound with the capsaicinoid functional structure, provided by the invention, has very good application prospects in preparation of marine antifouling coatings or antibacterial and mildew-proof coatings.