Emission rate of monoterpene and isoprene was measured in five commonly growing tree species of conifers(Pinus thunbergii, Abies koreana, Cryptomeria japonica, Pinus densiflora, Chamaecyparis obtusa) at the Halla mountain sites. Dynamic flow enclosure technique was used and gas samples were collected into Tenax tube. The highest and lowest hourly emission rate was observed in Abies koreana (1.86 ${mu}g$/gdw/hr) and Chamaecyparis obtusa (0.52 ${mu}g$/gdw/hr), respectively. The major species of monoterpene from pine trees were ${alpha}$-pinene, ${eta}$-pinene, ${eta}$-phellandrene, myrcene. Particularly, d-limonene was abundant in Abies koreana but ${alpha}$-pinene, $d^3$-carene and sabinene was in Cryptomeria japonica. Emission rates of isoprene show less significant than those of monoterpene. And also seasonal emission rates of monoterpene were dependent on environmental factors such as temperature.