The invention discloses a silica-based germanomolybdate heteropolyacid catalyst for iodine recycling and a preparation method thereof. The method comprises the preparation steps that a silicious porous material and a functional group coupling agent are added into a dilute acid solution with pH being 3-4, magnetic stirring is performed under the room temperature for 12-24 h, Keggin type germanomolybdate heteropolyacid, inorganic metal salt, a surface active agent and a dispersing agent are added, ultrasonic oscillation is performed for 0.5-1 h, the mixture is moved into a hydrothermal reactionkettle, a drying oven heated through a program is adopted, the reaction temperature is increased to 150 DEG C from the room temperature within 1 h, the temperature is kept for 48 h, then, natural cooling is performed to room temperature, hyper pure water and ethyl alcohol are adopted for washing repeatedly, filtering is performed, and drying is performed for 12 h. The catalyst can efficiently catalyze and peroxide iodine hydroxide ions to generate iodine substances, reaction conditions are mild, the hydrogen peroxide utilization rate is high, and the catalyst is environmentally friendly, freeof contamination, free of peroxidation, good in thermal stability, capable of being used repeatedly, and easy to recycle.