The invention provides a method for breaking down azeotropic distillation of tetraethyl orthosilicate and particularly relates to a method for breaking down the azeotropic phenomenon formed by methyltriethoxysilane, methoxy triethoxysilane and tetraethyl orthosilicate. The method comprises the steps that 1, a tetraethyl orthosilicate crude product is subjected to de-heavy rectification so as to obtain the tetraethyl orthosilicate after de-heavy rectification; 2, the tetraethyl orthosilicate after de-heavy rectification is mixed with a high boiling point solvent, then the mixture is subjectedto de-light rectification, and the tetraethyl orthosilicate after de-light rectification is obtained, wherein the boiling point of the high boiling point solvent is larger than or equal to 180 DEG C.Compared with the prior art, the method has the advantages that heave components are removed through de-heavy rectification first, then the tetraethyl orthosilicate is mixed with the high boiling point solvent for de-light rectification, the azeotropic phenomenon in the rectification process can be broken down, the solvent is more easily recycled, the rectification efficiency is improved, the rectification yield is increased, and energy consumption and equipment input are reduced.