The geometric and electronic structures at the interface between iron phthalocyanine (FePc) and Si(110) surface are studied by ultraviolet photoelectron spectroscopy and density functional theory (DFT) calculation.After FePc is deposited on Si(110),the emission features are located at 2.56,4.90,7.90,10.88eV below the Fermi level for monolayer and 2.73,4.90,7.74,10.52eV below the Fermi level for multilayer.At the coverage of 1ML,FePc molecules are adsorbed on the bridge site in a flat-lying geometry with a 2.17A separation between the molecule and the substrate.The molecular plane is bent due to the interaction between the adsorbate and the substrate.Metal phthalocyanine (MPc) and its derivatives have attracted a large amount of interest in the past couple of years.Phthalocyanine molecules have been extensively used as pigments,dyes and models of biologically important species such as porphyrins,hemoglobin,and chlorophyll.They have been used as the active elements in chemical sensors,[1-3] and are of great benefit for use in thin film transistors,[4-6]organic electronic devices[7-10] and solar cells.[11-14]