Accurate quartic anharmonic force field for perfluoromethanimine CF2NF has been calculated from the MP2method using a triple ζ basis set. The vibrational wavenumbers calculated using a variation-perturbationalgorithm agree for the fundamental bands very well with the experimental data. Our results predict a newinterpretation of some overtone bands observed in the medium infrared region between 250 and 3500 cm-1.