The invention relates to a distributed power heat supply system based on active disturbance rejection control and a method of the system. The method is characterized in that the distributed power heatsupply system serves as a controlled object for analysis, and the input and output amount and control amount are determined; through a tracking differentiator in active disturbance rejection control,the reference input of the controlled object is subjected to a transient process, and differential signals of the reference input are extracted; through an expansion state observer (ESO) in the active disturbance rejection control, uncertain factors and external disturbance in a distributed power heat supply system model are subjected to dynamic observation and estimation; through a nonlinear state error feedback control rule in the active disturbance rejection control, the control amount of the system is formed, and the anti-interference capability of the control is improved; all parts in the control process are subjected to parameter setting, so that the active disturbance rejection control method of the distributed power heat supply system is achieved. The distributed power heat supplysystem has a large effect of pushing forward the enforcement of the governmental policy and guideline about power replacement, the discharge of urban pollutants is significantly reduced, and the quality of the living environment of people is improved.