The invention discloses a system enabling boiler oxygen-rich combustion to be combined with an electrolytic hydrogen production peak and frequency regulation apparatus. The system comprises a power plant centralized control peak and frequency regulation control module, a boiler oxygen-rich combustion module, and an electrolytic hydrogen production peak and frequency regulation apparatus. The system improves the load reducing capability of a boiler itself and also enables a set to carry out in-depth peak and frequency regulation operations anytime during four seasons, so the flexibility of thethermal power set can be greatly improved. The system is widely applied to combined heat and power sets or pure condensing set. Moreover, environment pollution is low since clean fuels are provided bya power plant, power plant resources are utilized effectively, and the economical efficiency of the power plant is improved.