The invention relates to the field of large-scale new energy grid-connected power generation, and discloses a power flow sequence analysis model of an electricity-gas coupling comprehensive energy system. Under the condition of large-scale new energy grid connection, if the output of a new energy unit already meets the requirements of the EPS electrical loads, and according to a policy of preferentially consuming the new energy, all gas turbine units are stopped, the output of each new energy unit is solved, the new energy unit power which cannot be consumed by the EPS is solved, and the output is stored in an NGS via an electricity-to-gas conversion device and is substituted into a natural gas system, the power flow of the natural gas system is solved, the electric power required by a pressurizer is determined, and the power flow of a comprehensive energy system is solved iteratively. The model provides a theoretical basis for the normal and stable operation and the new energy consumption capability analysis of the comprehensive energy system.