An occupied electronic state induced by benzene adsorption on Cu(111) has been observed by means of two-photon photoemission (2PPE) spectroscopy measured with various photon energies from 4.05 to 4.37 eV. The 2PPE spectrum was composed of two features: one is fixed at an initial state binding energy of -0.3 eV relative to the Fermi level (E-F), the other, fixed at an intermediate state energy of 3.8 eV above E-F. The former arises from the bonding state between benzene and copper, the latter, from an image potential state on the benzene adsorbed surface. Photoemission from the adsorption-induced bonding state, which is weak in conventional one photon photoemission, is greatly enhanced by resonance with the image potential state. (C) 1999 Elsevier Science B.V. All rights reserved.