The energy industry accounts for a large proportion of carbon emissions and it is the main force of energy conservation and emission reduction. In order to ensure the sustainable development of the system, it is necessary to take carbon emissions into account when planning the integrated energy system. Under the backgound, an integrated energy system planning model is established in this paper considering carbon emission penalty factor. Firstly, according to the thermal and electrical load characteristics of a park, four planning schemes are proposed in this paper. The minimum net present cost is chosen as the optimization objective, the optimal capacity allocation of four planning schemes under the scenario of whether carbon emission penalty factor is considered or not. Secondly, the advantages and disadvantages of the four planning schemes are compared from the aspects of economic benefit and environmental benefit, and the thermoelectric coupling relationship of the integrated energy system is analyzed. Finally, the sensitivity of carbon emission penalty factors is analyzed. The results show that the carbon emission penalty factor can reduce the carbon emission of the integrated energy system, and the renewable energy, energy storage equipment and gas turbine can reduce the carbon emission and improve the environmental benefits.