Char and tar derived from pyrolysis of Uruguayan Eucalyptus wood has been evaluated as raw materials for the preparation of high mechanical resistance activated carbon pellets. Thermogravimetric analysis was used as the main technique for studying tar and char pyrolysis in N2 and CO2 atmospheres, and to determine the best conditions for CO2 activation of the carbon pellets. Results indicated that activated carbon pellets with high surface area and good mechanical resistance were obtained by CO2 gasification at 1098 K. Pellets properties can be explained as due to the independent contribution of each component.