This invention discloses a method for preparing additive for M80-M90 or E80-E90 alcohol-based automobile fuel. When 10-20 parts of the additive is added into 80-90 parts of methanol or ethanol, alcohol-based automobile fuel can be obtained, which can be used as a substitute for gasoline without the need for adjusting or replaing present engines. The alcohol-based automobile fuel has comparable power to commercialized leadless gasoline. Besides, a fuel energizer is added into the additive, which can convert methanol whose caloric value is 49% of leadless gasoline into automobile fuel with high power. |