Abstract: Lignocellulosic biomass is considered as one of the most promising feedstock for producing fuel ethanol. However, the structure and crystallinity of lignocellulose hamper the accessibility of cellulose enzyme, so that a suitable pretreatment process is necessary. Recently, steam explosion, because of its low cost, low energy consumption and pollution-free has been received substantial attention. The influences of parameters in pretreatment by methods of steam explosion,such as:technologies of dilute acid steam explosion(DASE),dilute base steam explosion(DBSE),ammonia fiber explosion(AFEX)and compound steam explosion are described, and several steam-explosion pretreatments and equipments are discussed. Meanwhile the applied research of pretreatment for bioconversion to ethanol is also reviewed.