The reaction kinetics between COS and aqueous solutions of some heterocyclic amines have been studied at 303 K. The reaction of COS with 1,4-Diazabicyclo[2.2.2]octane (DAB) and 1,2-Dimethylimidazole (DMI) has been investigated in an intensely stirred batch reactor; the reaction between COS and aqueous solutions of 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) has been studied by means of the stirred cell technique. The reaction of COS with aqueous DMI and DAB was found to be extremely slow and the observed reaction order in the amine concentration was about 0.8. The overall reaction rate for the reaction of COS with aqueous DBU solutions was rather high, whereas the observed reaction order in the DBU concentration was found to be about 1.7.