The pyrolysis of softwoods (Pinus (P.) densiflora, P. koraiensis), hardwoods (Quercus acutissima and Liriodendron tulipifera) and nut shell of P. koraiensis was investigated using a thermogravimetric analyzer and fixed bed reactor. Thermogravimetric analysis showed that the maximum decomposition temperature of each biomass was influenced by the ash content and lignocellulosic composition of biomass. The activation energy values also varied according to the content of hemicellulose and lignin of each biomass. Large amounts of acids, such as acetic acid, were recovered from the hardwood pyrolysis reaction due to their high hemicellulose content. The nut shell of P. koraiensis and softwoods with a higher lignin content produced higher yields of phenolic compounds than the hardwoods.