The dark respiration, photosynthesis(CO₂ refixation), CO₂ balance and chlorophyll content of lst-year conelets and 2nd-year cones of Korean pine(Pinus koraiensis S.et.Z.) were investigated after pollination up to the end of maturation. The results obtained are as follows : 1. The growth of 1st-year conelet was 3.6㎝ in length. 2.4㎝ in diameter and 3.058 in dry weighs during the first year. The growth of 2nd-year mature cone was 13.5cm in length, 9.3㎝ in diameter and 141.0g in dry weight in the late of 2nd-year. 2. The refixation of carbon dioxide released from a cone by the dark respiration was less than 50 percent at light saturation through the growing period. The refixation of carbon dioxide released by dark respiration for one year was 7.3 percent in 1st-year conelets and 8.7 percent in 2nd-year cones. 3. The dark respiration rate of cones by increasing temperature was rapidly increased with increasing temperature up to 25℃. The dark respiration rate of cones was much higher in non-growing season than that in growing season at the same temperature. 4. The rates of dark respiration and CO₂ refixation, based on the dry weight, were much higher in 1st-year conelet than that in 2nd-year cone. 5. The CO₂ balance for a cone was negative from pollination to the end of maturation. The net dark respiration loss for a cone was 7.23g CO₂/year in 1st-year conelet and 164.8g CO₂/year in 2nd-year cone. 6. The respiratory loss efficiency for a cone(=CH₂O weight calculated by net dark respirationjdry weight of cone) for one year was 1.61 in 1st-year conelet and 0.81 in 2nd-year cone for one year. 7. The total chlorophyll content of surface scale of the cone was lower than 2㎎/g dw through the growing period, and chl. a/b ratio was 2 to 3.