The invention relates to a thermal power generating unit coal feed amount control method based on frequency modulation and peak regulation of a power grid. The method includes the following steps that a thermal power generating unit coal feed amount control loop interface based on frequency modulation and peak regulation of the power grid is added to a logical configuration coal feed amount control loop of an original coordination control system; logical configuration of a thermal power generating unit coal feed amount control loop based on frequency modulation and peak regulation of the power grid is carried out, and output of the logical configuration of the thermal power generating unit coal feed amount control loop based on frequency modulation is introduced to the thermal power generating unit coal feed amount control loop interface based on frequency modulation and peak regulation of the power grid to serve as feedforward signals for controlling the coal feed amount; the control system is put into actual operation, according to the real-time operation curve, relevant parameters of the thermal power generating unit coal feed amount control loop based on frequency modulation and peak regulation of the power grid are set online, and finally the expected control effect is achieved. By means of the existing DCS coordination control system, the real time performance is good, the on-site debugging process is simple, and project realization is facilitated. By judging the operating state of the unit, the coal feed amounts of the unit in different operation states are accurately controlled, fast load response of the unit participating in frequency modulation and peak regulation and the stability of main parameters are guaranteed, the labor intensity of operators is reduced, and the safety and the economical efficiency of operation of the unit are greatly improved.