If the integrated resource planning has the resources of the supply-side and demand-side in the planning process considered at the same time， it can realize the objective of minimizing the total cost. A linear programming model is presented to optimize the combination of power generation and demand-side management based on traditional electric power planning and relevant research achievements. This model is also the quantification of different demand-side management measures and takes into account five categories of constraints， i.e. system reliability， electricity demand， resource usability， resource operation and the pollutant emissions in the planning period. The validity of the model is finally demonstrated with an example and the results show that the total cost can be cut down to the lowest compared with that by traditional planning while greatly reducing the pollutant emission.