Carbon monoxide (CO) is produced by incomplete combustion of organic compounds. Its intoxication usually results from inhalation of fumes from improper heating stoves, motor vehicles, or smoke from fires. It can reversibly bind various heme-containing proteins such as hemoglobin, myoglobin, cytochrome p450 and cytochrome oxidases. Among them, it has a high affinity for hemoglobin (230e270 times more avidly than oxygen) with which it forms carboxy-hemoglobin (HbCO) leading to decrease in oxygen-carrying capacity followed by end-organ hypoxia. A tissue hypoxia may then result in transient or permanent damage of important organs like central nervous system and even death. CO poisonings from different reasons are an important cause of morbidity and mortality in Turkey. The purpose of this study on CO poisonings in Turkey is to sum up and analyze the best available researches in both forensic and clinical toxicology fields. This was achieved by synthesizing the results of Turkish and English papers on forensic and clinical CO poisoning cases conducted in universities, institutes, hospitals and other official or private organizations in Turkey. Total of 47,523 medico-legal autopsy data collected from 9 different forensic medicine branches and emergency rooms in different year intervals were reviewed and 980 CO poisoning cases were determined. To calculate the frequency of CO poisoning within all the autopsies carried out and fatal poisoning cases, the number of cases was divided by the total number of medico-legal autopsies and total fatal poisoning cases. The mean age of cases, the source of CO gas, the most common seasons and months, gender, and blood HbCO levels were also taken into consideration if the data is available. Under the light of the findings, we may suggest that determination of affecting factors in CO poisoning is going to be one of the key subjects for planning preventive interventions. (C) 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.