A beam of gold atoms was produced by heating the gold containing material by electrothermal method. Two UV laser beams then orthogonally irradiated the atomic beam, exciting the Au atoms to very high Rydberg states from their ground states (6S1/2). A high voltage pulsed electric field was applied to the interaction region approximately 200 ns after the laser pulse, it ionized the Au atoms into Rydberg states. By scanning the wavelength of laser in a certain range, the positions of 38 energy levels of Au atoms in n2D3/2 (n = 18-38) and n2S1/2 (n = 21-34; 36-38) series have been determined. the ionization limits of the n2D3/2 and n2S1/2 series were found to be ED = 74409.8 (3)cm-1 and Es = 74410.0(2) cm-1, respectively, by parametric fitting. The quantum defects of all these levels were also calculated.