The countries that are parties to the Kyoto Protocol submit annual inventories of greenhouse gases to the United Nations Framework Convention on Climate Change Secretariat. The reports comprise values of emission and removal of greenhouse gases from different sectors (energy, industrial processes and product use, agriculture, land use, land use change, and forestry, and waste). These reports are prepared by using the methodologies indicated in guides that are prepared by the Intergovernmental Panel on Climate Change. Among the guides, those that are forestry related include: guidelines for the land use, land use change, and forestry (LULUCF) sector reported in 2003 and for the agriculture forestry and other land uses (AFOLU) sector reported in 2006. According to these guidelines, carbon, which is stored in the biomass as stock or annually sequestered amounts, can be calculated by using various factors derived from growing stock or annual increment in forests. Similarly, the amount of carbon removed from the forest by fire, production, or illegal cuttings can also be estimated using such factors. In this study, the biomass expansion factor (BEF1) is determined as 1.212 for the conifers and 1.310 for the broadleaved species. Also the BEF2 was updated and determined as 1.326 for the conifers, and 1.262 for the broadleaved species. In this study, the biomass conversion and expansion factors (BCEF's) that are used in the AFOLU guide were also calculated.