Abstract: In view of the uncertainty of renewable energy output and load demand in the new power system,the source-load coordination is difficult,and it is difficult to establish a reasonable time-of-use electricity price. This paper proposes a dynamic modification mechanism of time-of-use electricity prices considering the uncertainty of source load. First,according to the volatility and uncertainty of renewable energy output,calculate the deviation of new energy grid-connected electricity;Secondly,according to the change characteristics of the demand side load,combined with the uncertainty of renewable energy generation,through the error calculation method of multiple uncertainty conditions,the probability density of the final output variable is obtained. Then,according to the electricity consumption reported by the load and the forecast electricity price,a power market price setting model with the uncertainty of the source load is established,and the dynamic correction of the time-of-use electricity price considering the uncertainty of the source load is carried out. Finally,the effectiveness of the method proposed in this paper is verified by actual data simulation.