The invention discloses a method for setting parameters of a speed governor of a direct current delivering-out system of a hydroelectric generating unit. The method comprises the following steps of establishing a model for analyzing stability of the speed governor of a water turbine; obtaining a transfer function of a power generator and an external system thereof, a transfer function of a linearized model of the water turbine, and a transfer function of a linearized model of the speed governor; solving a closed-loop transfer function corresponding to the model for analyzing the stability of the speed governor of the water turbine, and a closed-loop characteristic equation of the speed governor, and utilizing Routh stability criterion to obtain a transient descending rate value range and a buffer time constant value range for stabilizing a speed governing system; performing time domain simulation in the transient descending rate valve range and the buffer time constant value range for stabilizing the speed governing system, so as to obtain optimum parameters of the speed governor of the water turbine. The method has the advantages that by adopting the model for analyzing the stability of the speed governor of the water turbine, and combining the Routh stability criterion and the time domain simulation, the optimum parameters of the speed governor of the water turbine are finally obtained, and the robustness is stronger; the method is widely applied to the field of power.