The invention discloses synthesis of a porous ZSM-5 zeolite and gamma-Al2O3 composite material and preparation of a hydrodesulfurization catalyst and relates to the technical field of composite materials and the field of hydrodesulfurization catalysts. The composite material is roasted for 3-8 h at the temperature of 450-600 DEG C, and has the following properties that the content of porous ZSM-5 zeolite is 5-95 wt.%, the content of gamma-Al2O3 is 5-95 wt.%, the specific surface area is 400-600 m<2>.g1, the mesopore volume is 0.40-0.85 cm<3>.g1, and the micropore volume is 0.06-0.15 cm<3>. g1. The composite material has multiple stages of porous structures, good hydrothermal stability, high mechanical strength and weak interaction with loaded metal species, changes the existence state of the metal species and promotes reducing and vulcanizing of the metal species, multiple layers of high-activity molybdenum sulfide or tungsten sulfide active phases are easily formed on the composite material, and the hydrodesulfurization performance of the metal sulfide catalyst is improved.