The invention discloses an oil-saving decarbonization additive for a fuel vehicle. The oil-saving decarbonization additive is prepared from 50 to 75 percent of methanol, 2 to 8 percent of n-butyl alcohol, 1 to 2 percent of isobutyl alcohol, 1 to 3 percent of tert-butyl alcohol, 1 to 2 percent of polysorbate, 1 to 2 percent of sodium dodecyl benzene sulfonate, 2 to 3 percent of oleic acid, 5 to 10percent of petroleum ether, 1 to 2 percent of triethanolamine, 2 to 6 percent of ethanediol, 2 to 5 percent of octanol, 1 to 4 percent of ethane, 1 to 3 percent of ethanol, 1 to 2 percent of compositemetal corrosion inhibitor and 0.5 to 2 percent of rubber and plastic anti-swelling protective agent. The oil-saving decarbonization additive disclosed by the invention does not require a complicatedtechnology, can be prepared into fuel which can be directly used by vehicles by being simply adding in an alcohol ether stock solution, and can be immediately prepared during use; the oil-saving decarbonization additive is stable in characters and can be stored for standby use for a long term under a sealing condition, and compared with gasoline and diesel oil, requirements on conditions for transportation and storage of the oil-saving decarbonization additive are lower; the oil-saving decarbonization additive can also be used as a burning promoter of finished gasoline and diesel oil, the concentration of carbon monooxide, hydrocarbon and oxynitride in tail gas can be reduced, the burning rate and the burn-off rate of the gasoline and the diesel oil can be increased, and emission of the tail gas can be reduced.