NOVELTY - Producing fuel ethanol using Lycoris plant, where the corms of the Lycoris plant are the raw materials to produce the fuel ethanol and the by-product amaryllidaceae alkaloid is produced comprises: (a) screening and washing the raw material Lycoris radiate corms; (b) crushing; (c) enzyme acid liquefying; (d) filtering; (e) concentrating in vacuum; (f) removing the alkaloid; (g) saccharifying; (h) fermenting; and (i) distilling and rectifying.    USE - The method is useful for producing fuel ethanol using Lycoris plant (claimed).    ADVANTAGE - The invention can convert more than 95% starch in the L. radiate to alcohol; it has simple process flow, little used time, easy operation and no pollution.    DETAILED DESCRIPTION - Producing fuel ethanol using Lycoris plant, where the corms of the Lycoris plant are the raw materials to produce the fuel ethanol and the by-product amaryllidaceae alkaloid is produced comprises: (a) screening and washing the raw material L. radiate corms: the spherical bulbs of the Lycoris plant with high starch content without mildew, rot and insect pest are selected to wash, remove impurities and weigh to obtain the materials; (b) crushing: water with 2.6 to 3.0 times of weight of the materials is added; the L. radiate corms are smashed by the crusher and preheated 30-60 minutes at 70 degrees C; (c) enzyme acid liquefying: the smashed materials are stirred in the reaction kettle with dilute sulfuric acid; alpha-amylase is added; the sulfuric acid concentration is 0.4-0.7%; the mass ratio between the materials and the sulfuric acid water is 1:3 to 1:2; the adding quantity of the alpha -amylase is 1-3wt.% of the materials; the temperature is maintained at 90-93 degrees C; the liquefying time is 4-6 hours; the liquefied mash is produced; (d) filtering: the residue is removed by filtering, and the filtrate is kept; (e) concentrating in vacuum: the filtrate is regulated pH value to 6-7 with 1:1 ammonia liquor, and is concentrated in vacuum to 1.1 to 1.2 specific weight, then is regulated pH value to 9-11 with 1:1 ammonia liquor; (f) removing the alkaloid: acetic ester with 3-6 times of concentrated solution volume is used for dynamic reflux extracting; the organic phase is reserved for producing the alkaloid; the water phase is regulated pH value to 5.1-5.6 with 1:1 hydrochloric acid liquor, then is concentrated to 1/4 to 1/5 of the original volume to obtain the concentrated acid regulating solution; (g) saccharifying: the assistant raw material husk is added in the concentrated acid regulating solution, the adding weight is 30-35% of the concentrated acid regulating solution; then the saccharifying enzyme that is 2% of the total quantity of the husk and the concentrated acid regulating solution is added; the pH value is controlled within 5.0-5.5; the saccharifying mash is obtained after saccharifying 8-10 hours at 65-70 degrees C; (h) fermenting: the active yeast liquid that is 1-3% of the saccharifying mash weight is added in the saccharifying mash to ferment; and (i) distilling and rectifying: after the yeast changes sugar to alcohol, the alcohol in the fermented mash liquid is distilled out by using the traditional method; the fuel alcohol is obtained by primary distilling and rectifying.