Abstract: Based on historical data,the distribution function of wind and photovoltaic power forecasting error at different output levels is fitted. The Spearman correlation coefficient is introduced to describe the complementarity of the wind and photovoltaic power forecasting error by season,so as to obtain the joint wind and photovoltaic power forecasting error distribution model. Then,the changes in dispatch cost caused by joint forecasting error of wind and photovoltaic power is considered,and the forecast error cost is introduced into the objective functions of the day-ahead and real-time electricity market dispatching models. Thus,a more reasonable electricity spot market dispatching model in statistics is proposed. An example is used to analyze the impact of forecast error cost,forecast error complementarity,and distribution coefficient of wind and photovoltaic forecast error on the scheduling results. The rationality and effectiveness of the model is illustrated in the example.