Carbofuran, known as 2, 3-dihydro-2, 2-dimethyl-7-benzofuranyl- N-methylcarbamate, is a broad spectrum N-methyl carbamate pesticide. Carbofuran and its metabolite, 3-hydroxycarbofuran, exert their toxicity by reversibly inhibiting acetylcholinesterase (AChE). Carbofuran is widely used in agriculture for pest control. Agricultural workers and the general population may beexposed to it by dermal contact, inhalation, or ingestion as a result ofits application or by food intake. To better characterize the human health risk caused by carbofuran exposure, a physiologically-based pharmacokinetic/ pharmacodynamic (PBPK/PD) model was developed in the Exposure Related Dose Estimating Model (ERDEM) system in order to facilitate an understanding of carbofuran's absorption, distribution, metabolism, elimination (ADME) processes, and AChE inhibition effects for the rat. To obtain relevant experimental measurements and the estimates of physiological, biochemical, and physicochemical parameters for the model, literature reviews were conducted. The focus was placed on oral exposure and modeling carbofuran metabolism in the liver to 16 known metabolites, the enterohepatic circulation of glucuronide conjugates, and the excretion to urine and feces. Cholinesterase inhibition by carbofuran and 3-hydroxycarbofuran is modeled in the bloodand brain.