Applying scientific and effective evaluation methods to evaluate the planning scheme of an integrated energy system (IES) can provide a crucial guarantee for its reasonable construction and operation. First, this paper analyzes the energy architecture and operation mode of an IES in industrial parks under the dual carbon goal and constructs a comprehensive evaluation index system covering the three aspects of economy, technology and environment. This is after organically integrating its multi energy complementary characteristics with carbon emission reduction and a carbon trading mechanism. Then, given the operational uncertainty of an IES, the basic framework of comprehensive evaluation is established based on a cloud matter-element model, and two improvements are made to overcome the shortcomings of the practical application of the model. On the one hand, considering the acceptability of fuzziness by evaluators, the calculation method of cloud entropy parameters is optimized; on the other hand, based on the minimum discriminant information principle, the decision-making trial and evaluation laboratory (DEMATEL) and CRITIC methods are combined to solve the bias problem attributable to a single weighting method, and a more sensible combination weight is obtained. Finally, an example is given to verify that the proposed evaluation method can effectively solve the evaluation problems caused by the long board or short board effect of traditional matter-element evaluation and the uncertainty of system operation.