Abstract: Coriolis mass flow meters are widely used in energy trade and industrial production. CFD simulation software was used to simulate and calculate the calibration conditions of Coriolis mass flow meters with the same and different specifications in series in this paper. The flow conditions and resistance coefficients of the series flow meters in the pipeline are analyzed. The results show that, when the overall structure of the pipeline remains largely unchanged, the flow rate in a series pipeline is influenced by the pressure difference between the gas source and the gas tank. When two flow meters are connected in series, the differences in mass flow rates and resistance coefficients between the upstream and downstream sections are minimal. However, when different specifications of flow meters are connected in series, the differences in mass flow rates and resistance coefficients between the upstream and downstream sections are more pronounced. By analyzing the reasons for the differences in mass flow rates between the upstream and downstream sections when two flow meters are connected in series under various operating conditions, this analysis provides a reference for improving the calibration accuracy of Coriolis mass flow meters. It is of great significance to improve the fairness of energy trade and the security of industrial production.