Most of rice straw produced as a byproduct is not or low utilized in Japan. However, it may be available for the production of bio-ethanol without threatening food supply because of its characteristics as one of the lignocellulosic materials. Though it has already been revealed in previous studies that bio-ethanol made from rice straw can contribute to reducing energy consumption and repressing greenhouse gas emissions, effects on ecosystem due to land occupation for rice straw production and ethanol refinery plant have not been evaluated. Thus, environmental impacts of bio-ethanol made from rice straw including effects on ecosystem caused by land occupation were evaluated in this study.
 Some differences among three representative assessment methods could be found in results of the effect on ecosystem due to land occupation for rice straw production and ethanol refinery plant. However, it is common among all assessment methods that the effect on ecosystem caused by land occupation dominates large part of total environmental impact of ethanol made from rice straw (72-83% of total impact). Bio-ethanol made from rice straw showed larger environmental impact compared to that of gasoline due to land occupation. The improvement of the operating rate and the productivity of ethanol refinery plants is especially necessary for repressing the environm ental impacts related to bio-ethanol production made from rice straw.