In view of the inconsistency and incompatibility in the calculation results of the EMU assignment, the undertaking of the EMU maintenance workload of the EMU depot(station), and the scale of the maintenance facilities in the newly built high-speed railway hub, this article proposes, Three methods for measuring the size of the EMUs in the hub using the full turnaround time and daily train-kilometer method as indicators. Focusing on the daily EMU-kilometres and full turnaround time as the main indicators to calculate the size of the EMUs in the hub，it explores the overhaul workload of the EMU depot(station) and the method for calculating the scale of overhaul facilities. The research results show that the calculation results using the daily train-kilometer index of EMUs have a large margin, and it is necessary to rationally adjust the average daily shape-kilometer indicators of the EMUs in the hub based on the main technical standards of the railway in the hub, passenger flow, and driving plan. However, the calculation method is more convenient and suitable for long-term railway hub planning investment and EMU vehicle production scale control. The calculation results using the full turnaround time index of EMUs are more scientific and reasonable, which can effectively improve the utilization rate and operation rate of EMUs. At the same time, it can effectively reduce the waste of maintenance resources and the investment in engineering construction in terms of operation and maintenance.