The invention relates to a method for evaluating the frequency modulation urgency of a generator set. The method comprises acquiring the frequency fluctuation characteristics of the grid according tothe steady-state operation data of a regional power grid, and acquiring the transient frequency fluctuation characteristics of the grid according to the transient simulation data under the typical fault of the regional power grid; in combination with the dead zone setting of a nuclear power unit and the installation proportion of the nuclear power unit, obtaining the frequency modulation urgency of the nuclear power unit required by a power system; and according to the frequency modulation requirements of different types of generator sets and the operating characteristics of the sets, achieving that the regional power grid participates in the primary frequency modulation control strategy of the power system.