A processing method for ultra-thin single-crystal germanium wafers is characterized by the following steps: first, single crystal germanium wafers with a thickness of less than 0.5 mm are cut from the single crystal germanium rods using a linear cutting equipment;Secondly, the single crystal germanium chip is loaded into the low temperature polishing machine.Third, first use diamond, corundum, silicon carbide, boron carbide and other hard abrasive with mohs hardness greater than 9 with particle size of 10-28 displacement m as the polishing head for rough machining, and use anhydrous organic solvent as the polishing liquid.Fourth, to switch to size 0.06 ~ 2 microns CeO2, silica and other mohs hardness less than 9 freezing consolidation abrasive abrasive pads as polishing finishing with a polishing head for secondary processing, polishing temperature control in 30 ~ - 10 ℃, polishing pressure control in 100 ~ 500 g/cm2, polishing solution for anhydrous organic solvents, flow rate of 50 ~ 500 ml/min, the polishing speed is 10 ~ 300 r/min, finally get the thickness less than 0.15 mm slim of germanium.The invention has simple method and high yield.