Abstract: Coal-fired power generating units undertake important peak regulating tasks in the power system. In order to improve their response speed under the rapid load change, this study proposes the peak regulating control optimization technology for coal-fired power generating units. First, a comprehensive cost function including coal consumption, start and stop, mechanical loss, fuel combustion, environmental surcharge and penalty cost is constructed as the goal of peak regulation control optimization. Then, a number of constraints including power output, climbing rate, start and stop time, coal consumption rate, pollutant emission and reserve capacity are clarified. Finally, the particle swarm optimization algorithm is used to solve the model parameters to find the optimal peak modulation control strategy that can satisfy all the constraints and minimize the comprehensive cost. The experimental results show that the studied technology can effectively improve the peak regulation response speed of the coal-fired thermal generating units, meet the design standards, and ensure that the unit maintains efficient and stable operation under the complex load changes.