A thermochemical hole burning (THB) effect was observed on two organic charge transfer complexes, when applying a suitable voltage pulse using a scanning tunneling microscope (STM), which is closely related to a STM current-induced localized thermochemical decomposition of the charge-transfer complex. The decomposition reaction evolves the low boiling point decomposition components of the charge-transfer complex, leaving a nanometer-sized hole on the crystal surface. This effect demonstrates the possibility of creating an ultrahigh-density THB memory, in which information bit is recorded as a hole.