The invention aims at providing an ethyl alcohol reforming system and an ethyl alcohol reforming control method for improving dynamic performance of a natural gas engine. The ethyl alcohol reforming system for improving the dynamic performance of the natural gas engine comprises an LNG (liquefied natural gas) storage tank, an LNG vaporizer, a mixer, a turbine supercharger, an ethyl alcohol storagetank, an ethyl alcohol vaporizer and an ethyl alcohol reformer, wherein a gas compressor in the turbine supercharger is connected with the mixer through an intercooler, the LNG storage tank is connected with the LNG vaporizer through a liquified natural gas flow valve, the LNG vaporizer is connected with the mixer through a gaseous natural gas flow valve, the mixer is connected with a gas inlet pipe, the gas inlet pipe is connected with a turbine of the turbine supercharger, a gas discharge pipe is connected with the ethyl alcohol reformer through a waste gas bypass pipe, a waste gas bypass valve is connected onto the waste gas bypass pipe, the ethyl alcohol storage tank is connected with the ethyl alcohol vaporizer through a liquified ethyl alcohol flow valve, the ethyl alcohol vaporizeris connected with the ethyl alcohol reformer, the ethyl alcohol reformer is connected with the mixer through a reforming pipeline, and a reformed gas flow valve is installed on the reforming pipeline. The ethyl alcohol reforming system and the ethyl alcohol reforming control method for improving the dynamic performance of the natural gas engine can effectively inhibit engine knocking and accidentfire phenomena of the natural gas engine, and also can achieve efficient combustion under cold start and low load work conditions and loading work conditions.