The effective propagation of multi-cluster fractures in horizontal wells is the key to the development of unconventional reservoirs. Due to the influence of pressure drops at perforating holes and the stress shadow effect, it is difficult to predict the fracturing fluid distribution and fracture dimensions in a fracturing stage. In this paper, a two-dimensional fluid-solid coupling model for simultaneous propagation of multiple fractures is established, and fluid distributions and dimensions of multiple fractures are studied with respect to different perforation designs. The model combines the User Amplitude Curve Subroutine (UAMP) in ABAQUS and the cohesive zone model (CZM) to calculate the perforating friction, fluid distribution and fracture propagation behaviors. After the accuracy of this model is verified by the analytical solution, a group of simulation is conducted to compare fracture propagations when the conventional limited-entry method (CLE) and extreme limited-entry method (less than 5 perforations per cluster, XLE) are used. Simulation results show that the edge and sub-central fractures in CLE cases almost get all the fluid and effectively propagate; central fractures receive little fluid and hardly propagate. In XLE cases, the fluid distribution of each fracture is relatively uniform, but the fracture lengths within one fracturing stage is still uneven; however, only reducing numbers or radii of perforation holes cannot achieve the uniform fracture propagation, where diverters might be further needed. Findings of this study provide a reference for the perforation optimization of multi-cluster horizontal wells in the field.