A millimeter wave equivalent circuit model parameters extraction method for Schottky diodes is proposed in this paper. The pad capacitance has been determined by using open circuit test structure， and the feedline inductance has been determined by using short-circuit test structure. The parasitic resistance has been extracted by using DC method and AC method respectively. An excellent fit between measured and simulated S-parameters in the frequency range of 1～40 GHz is obtained for GaAs Schottky diode．