The infrared spectrum of gaseous CF3NO has been studied in the region 4000–35 cm−1. The infrared spectrum of the condensed phase has also been recorded and a complete vibrational assignment is proposed. Attempts to record the Raman spectrum have been hampered by photolysis. A frequency of 50 cm−1 for the CF3 torsional mode has been estimated from combination and hot bands. This corresponds to a barrier to internal rotation of approximately 425 cal/mol (150 cm−1). A normal coordinate analysis has been carried out and potential energy distributions, and valence and symmetry force constants are reported.