Comparative analysis of resource input for ethanol produced from corn and sugarcane in temperate, dry, and tropical climate zones was conducted. Parameters such as the Net Energy Value (NEV), water requirement, land requirement, carbon dioxide emission with and without impact of changes in land use, and fertilizer released to the environmentas surface runoff for nitrogen and phosphate, were compared for corn and sugarcane ethanol production. The estimates of NEV for corn ethanol varied from -462 to 1757?kJ?l-1, while those of sugarcane ethanol were between 16?057 and 17?092?kJ?l-1 for the three climatic zones considered in this study. The results of the study also indicate that ethanol produced from sugarcane uses less or comparable amount of resources in contrast to ethanol produced from corn. Copyright (c) 2011 John Wiley & Sons, Ltd.