Given the background of "double carbon", and to promote the renewable energy consumption rate and settle the problem of low-carbon energy supply in the integrated energy system, an economical and low-carbon dispatch strategy for a hydrogen-containing integrated energy system for thermal power units to participate in the purchasing trade for a green certificate is proposed. First, the integrated energy system is modeled according to the coupling relationship between the CSP station and the electric hydrogen production system. Then, a green certificate trading model with thermal power units as its purchasers is established. With the support of carbon trading, the green certificates purchased by thermal power units can be converted into carbon quotas. Then, from the green certificate trading price, a pricing mechanism is proposed considering the green certificate’s relationship of supply and demand, and its purchasing volume is adjusted based on the price changing. Finally, an optimal dispatch model aiming at minimizing the total operating cost of the hydrogen-containing integrated energy system is established. Simulation analysis shows the dispatching strategy proposed in this paper can increase the green certificate purchasing demand and renewable energy consumption rate, and achieve the goal of low-carbon economic operation of the system. This work is supported by the National Natural Science Foundation of China (No. 51777027).