The invention discloses silicon-containing benzocyclobutene monomers, such as dimethyl vinyl benzocyclobuten-1-ylsiloxane, and a preparation method thereof. The preparation method of the compound comprises: adding magnesium, anhydrous lithium chloride and lithium aluminum hydride into a reactor under water-free, anaerobic and nitrogen-protection conditions; dripping the tetrahydrofuran solution of 1-bromobenzocyclobutene with stirring, dripping the tetrahydrofuran solution of methylvinyldichlorosilane after the magnesium is reacted completely, and reacting at -20 to 40 DEG C for 3 to 24 hours; and adding water to terminate reaction, extracting with an organic solvent, drying an organic phase by using an organic salt drying agent, concentrating, and subjecting the concentrated material to reduced-pressure distillation or silica column chromatography to obtain a product. The compound contains reactive vinylsilyl and hydrosilyl reaction groups, and the high polymer material formed by reaction has high comprehensive performance and has great development potential and application prospect in fields of microelectronics, aerospace and national defense.