The invention discloses a composite solid base catalyst, which is mainly made of components with the following mass ratio: carrier: γ‑Al  2 o  3 100 parts, loading components: 0.5-5 parts of binder, 1-25 parts of magnesium-containing compound, 1-25 parts of calcium-containing compound, 0.5-5 parts of polyacrylamide, 0.1-2 parts of inorganic base; the binder is  One of the following: glycerin, starch, methylcellulose, polyacryl alcohol, aluminum sol, water glass; magnesium-containing compounds are one of the following: MgO, Mg(OH)  2 , MgCO  3 , Mg(OAc)  2 , MgCl  2 ;Calcium-containing compound is one of the following: CaO, Ca(OH)  2 , CaCO  3 , CaCl  2 ; The inorganic base is one of the following: NaOH, KOH, Na  2 CO  3 、K  2 CO  3 .  The obtained catalyst is used for the preparation of guaiacol glyceryl ether, the operation is simple and environment-friendly, the energy consumption is small, and the yield is high.