Normal values of carboxyhemoglobin will be acquired by more studies. The authors now report the normal values of carboxyhemoglobin in Woosok Hospital of 108 random cases sampled from physical examine at Woosok Hospital by the Heilmyer-modified method. The results obtained are as follows ; 1. Of 108 random cases, 79% is under the value of 2.9% Co=Hb and 45.37% belonged to the level of 0-0.9%. 2. Mean value of carboxyhemoglobin was 1.52%-1.77 and this shows no significant relationship with hemoglobin level. 3. Considering sex, the level of carboxyhemo globin was slightly higher in male than in female.