Abstract: Hydrogen-enriched compressed natural gas technology can reduce the carbon emission of the system, but the fluctuation of the hydrogen mix ratio may lead to the safety hazard of natural gas pipeline operation. Therefore, a low-carbon safety analysis method for an electric-gas-hydrogen-integrated energy system based on the "region" model is proposed. Firstly, the calculation model of steady-state energy flow and carbon flow of the electric-gas-hydrogen integrated energy system is established, and the distributed iterative solution algorithm of steady-state energy flow and carbon flow is proposed. Secondly, the energy carbon security region model of an integrated energy system considers multi-energy carbon flow constraints, and its evaluation index is defined and established. The visual solution process of the energy carbon security boundary is given. Finally, a numerical example is given to verify the model's effectiveness. The proposed energy carbon security region model can effectively reflect the system's safe operation state and low carbon operation level under different hydrogen mix ratios and provide theoretical support for the low carbon safe operation of the integrated energy system.