A case of Occupational Mercury Poisoning Chung Yill Park, Chee Kyung Chung, Kwang Mook Lee and Seung Han Lee Catholic Industrial Medical Center,Catholic University Medical College, Seoul, Korea. The diagnosis of occupational mercury poisoning will depend on the exposure history, clininal symptoms and sings, laboratory findings and other informations such as laboratory results of other workers who have been worked under the same working condition. We diagnosed a 15 year-old male patient, who had been worked for 12 days at mercuny thermometer workshop, as occupational mercury poisoning by putting the above mentioned diagnostic bases together and reported here with brief rewiew of literature.