With the proposal of "double carbon" goal, energy and environment problems are becoming more and more prominent. In this paper, a day-ahead interval optimization strategy is proposed for integrated energy system that takes into account of the carbon emissions and waste-to-energy generation. The structure of the integrated energy system with waste-to-energy generation is analyzed, and the treatment of carbon emissions in the system is also analyzed. For the uncertainty of renewable energy output in the system, the interval number is proposed to represent the uncertainty of renewable energy output, and an operation model of waste-to-energy generation is constructed. Afterwards, a day-ahead interval optimization model of integrated energy system is constructed with the objective of minimizing the operating cost and fuel cost of different equipments. Finally, an integrated energy system containing waste-to-energy generation is validated, and sensitivity analysis is performed on the interactive power and energy storage capacity. The results show that the proposed method has better economy, accuracy, and the proposed method has better panoramic feasibility.