Replicated field experiments were conducted at three locations in North Carolina to study the disappearance of parathion from flue-cured tobacco. Immediately after application, parathion residues on green leaves, averaged over locations, were 51.0 and 78.8 ppm, respectively, for the 0.56 and 1.12 kg/ha rates. These residues dropped to 0.63 and 1.50 ppm for the two rates at five days after application. Parathion residues disappeared from green leaves most rapidly during the first 24 hr after application; the loss was over 95 percent in five days and over 99 percent at nine days after application. Residues of paraoxon on green leaves were highest one day after application when concentrations averaged 1.4 and 3.0 ppm for application rates of 0.56 and 1.12 kg/ha, respectively. Loss of total parathion residues during flue-curing ranged from 53 to 87 percent with an average of 72 percent.