This paper reports the results of a two-laser resonance enhanced photoionization experiment of Benzene molecule. The excitation was done by two frequency doubled dye lasers. The first laser pumped the molecule to a selected singled state (S -1), from where it was ionized by a time delayed pulse of the second laser. The ion quantum yield depends on the intermediate vibronic state as well as on the wavelength of the ionizing laser. From the structure and intensity of the measured ion spectrum we derived vibrational frequencies and molecular parameters of tlie ground electronic state of the ion to a high precision. The contributions of autoionizing Bydberg Levels to the ionization cross section can dlearly be distingnislied. from direct ionization some of these resonance peaks could be assigned to vibrations within these Rydber states.