The electronic and chemical structure of the interface between the amino acid (L)-cysteine and Au was determined by photoemission spectroscopy (PES). (L)-Cysteine was deposited by repeatedly dipping Au substrates into solutions of (L)-cysteine in methanol with various concentrations. To enable repeat deposition without significant contamination, the dipping procedure was performed in a glovebox directly connected to the ultrahigh vacuum (UHV) chamber in a N-2 atmosphere. X-ray photoemission spectroscopy (XPS) measurements between deposition steps allowed to characterize the chemical interaction at the interface to be characterized. Ultraviolet photoemission spectroscopy (UPS) measurements yielded the orbital lineup at the interface as well as the highest occupied molecular orbital (HOMO) structure Of L-cysteine. The charge injection barrier between the L-cysteine HOMO and the Au Fermi level was found to be 3.0 eV. The interface dipole between the Au substrate and the (L)-cysteine overlayer was determined to be 1.03 eV. The results also indicate the formation of an interface state similar to 1.5 eV above the HOMO of the (L)-cysteine.