Electronic states and atomic structure at the Pd2Si–Si interface have been investigated using AES and UPS in conjunction with transmission electron microscopy (TEM). By following the core and valence spectra from submonolayer to several atomic layers of Pd coverages, the changes in the partial state density of the Pd and Si atoms during interface formation have been observed. Stoichiometry calibration based on relative variation of Auger intensities reveals extra Si states existing within a few Å of the interface. Analysis of the spectral shapes and peak shifts shows that these Si states are derived from a Si‐rich environment at the interface and are located mostly near the Si bandgap region. TEM lattice images reveal a structurally sharp Pd2Si–Si (111) interface with misfit dislocations and atomic steps present within several Å of the interface. Combining the spectroscopy and TEM results, we infer that the interface states originate from chemical bonds associated with the atomic defect structures produced by silicide formation.