This research conducted the life cycle inventory analyses of biofuels in Taiwan. The biofuels considered include bioethanol production from sugarcane as well as biodiesel production from soybean and rapeseed. Energy inputs and pollutant emission (including carbon dioxide) are the input/output items analyzed. Results obtained from the inventory analyses can be summarized as follows. Bioethanol production from per hectare sugarcane cropland is 5160L (liters), meanwhile, 476 and 1012L biodiesel can be produced from I ha of soybean and rapeseed, respectively. The energy input to produce a liter ethanol, a liter biodiesel produced from soybean and rapeseed are 1256, 9602 and 5191 kcal, respectively. Those energy inputs are still less than the energy content of ethanol or biodiesel. It can be concluded that there is a positive energy benefit in producing biofuels based on a comparison with the previous work. In addition, through their life cycle, 1478.4 kg CO2 emission is generated from one hectare of soybean land and 2954.1 kg is generated from rapeseed land. Life cycle carbon dioxide emissions released from burning ethanol is 0.08 kg/LOE in contrast to 2.6 kg/LOE released from burning fossil gasoline. (C) 2008 Elsevier Ltd. All rights reserved.