Organophosphate compounds are predominant group of insecticides used for pest control in many parts of the world. Organophosphates inhibit both true cholinesterase and pseudocholinesterase. Organophosphates cause poisoning as a result of the excessive accumulation of acetylcholine at the cholinergic synapses due to inhibition of acetylcholinesterase. In the literature, it has been reported that there have been electrocardiographic abnormalities, including QT interval prolongation in most patients with organophosphate poisoning. In this paper, our aim is emphasize relationship between blood cholinesterase levels and QTc interval after organophosphate intoxication in the light of recent reports.