NOVELTY - A organic waste preprocessing device for preparing vehicle fuel, comprises a feeding pump, a heating device, a anaerobic fermentation device, a secondary anaerobic fermentation device, a desulfurizing device, a marsh gas compressor, a buffer tank, a three level filter, membrane separation device, gas compressor, gas column or machine connecting pipeline and a feeding port.    USE - As organic waste preprocessing device for preparing vehicle fuel (claimed).    ADVANTAGE - The organic waste preprocessing device produces marsh gas that can be directly used as compressed natural gas (CNG) automobile fuel, and improves the additional value of the marsh gas.    DETAILED DESCRIPTION - A organic waste preprocessing device for preparing vehicle fuel, comprises a feeding pump, a heating device, a anaerobic fermentation device, a secondary anaerobic fermentation device, a desulfurizing device, a marsh gas compressor, a buffer tank, a three level filter, membrane separation device, gas compressor, gas column or machine connecting pipeline and a feeding port; where the feeding port is connected with the feeding hole of pump of the preprocessing device, where the feeding pump is connected with the secondary anaerobic fermentation device, where the secondary anaerobic fermentation device connect with a material overflow port and first air outlet, where the heating device through pipeline connect with the secondary anaerobic fermentation device, where the material overflow port through a pipeline connect with the second secondary anaerobic fermentation device, where the first air outlet through pipeline connect with the second secondary anaerobic fermentation device, where the second secondary anaerobic fermentation device connect with second air outlet, where the air inlet pipeline of the desulfurizing device connecting with the air inlet of the desulfurizing marsh gas compressor device, where the air outlet of gas compressor device connected with the buffer tank, where the air inlet of the marsh gas compressor connecting with the air outlet of the filter, where the air outlet is connected with the membrane separation device, where the heating device is connecting to gas compressor, where the membrane module connecting with machine or filling column of gas compressor connect.