The purpose of this study was to investigate the effect of flunitrazepam, a benzodiazepine with strong hypnotic properties, on dream content. Eight normal subjects were studied in laboratory by the awakening technique, and the dream contents were rated by two judges according to nine scaled dimensions: unreality, participation of the dreamer, pleasantness, unpleasantness, verbal aggressivity, physical aggressivity, sexuality, sensoriality and time of reference in the dreamer’s life. By comparison with placebo condition, flunitrazepam induced more unpleasantness, more verbal aggressivity, more physical aggressivity, and more sexuality in dreams. This increase of emotionally loaded contents can be related to a disinhibitory effect of this drug, and the possible involvement of dopaminergic or serotoninergic systems is discussed.