The reactions of CF3O-, CF3OHF- and CF3OH2O- with ClONO2 have been studied in the temperature range 225-325 K. The reactions of CF3O- and CF3OH2O- with ClONO2 proceed at the collision rate whereas the reaction of CF3OHF- with ClONO2 is slower. No significant temperature dependence of the rate constant has been found for each reaction. The mechanistic study has shown that the reaction of CF3O- with ClONO2 proceeds by fluoride transfer and the product of the reaction between CF3OH2O- and ClONO2 is the cluster ion CF3OClONO2 -. The equilibrium reaction of CF3O- with H2O has been also studied between 262 and 295 K. Values of -63.2 ± 6.7 kJ mol-1 and -114.6 ± 23.9 J mol-1 K-1 were derived for the standard reaction enthalpy and entropy, respectively.