The invention relates to the technical field of hydrogenation catalyst supports, and particularly discloses a method for preparing a Pd hydrogenation catalyst composite support. The method for preparing the Pd hydrogenation catalyst composite support is characterized by comprising the steps that an additive and a solvent are mixed to be prepared into a support blender; pseudo-boehmite, silicon dioxide and inert aluminum oxide powder are evenly mixed to serve as a raw material for preparing the support; the raw material and the blender are mixed and kneaded into extruded strips according to the mass ratio of (1-3):1, the extruded strips are dried and then calcined, pelleting is carried out, and the support is obtained. A product of a specific workshop section processed through a catalyst prepared from the support on finished C5 serves as a raw material for saturated hydrogenation, reaction conditions are mild, the hydrogenation efficiency is high, the optimal catalyst olefin conversion rate is not lower than 98%, the pentane content of the hydrogenation product is not lower than 97%, and good industrial application prospects are achieved.