The invention provides a synthesis method of tackifier containing boron. The synthesis method is characterized by comprising the following steps that (1), the following raw materials are prepared: silane monomers, a double end blocking agent, borate ester, solvent, an acid catalyst and a neutralizer; (2), the silane monomers, the borate ester, the acid catalyst and the solvent are mixed evenly, under the conditions of nitrogen protection and condensation reflux, the hydrolysis reaction is conducted for 5-10 h at a temperature of 40-100 DEG C, and a first mixed material is obtained; (3), the double end blocking agent is added to the first mixed material obtained in step (2), the reaction is continued to conduct for 0.5-3 h, and a second mixed material is obtained; (4), the neutralizer is added to the second mixed material obtained in step (3), neutralization reaction is conducted, and a third mixed material is obtained; (5), then, the third mixed material obtained in step (4) is filtered and purified, then by adopting reduced pressure distillation, the solvent is removed, and the tackifier containing boron is obtained. The method can greatly improve the bonding strength of an additive silicone rubber adhesive sealant.