In order to solve the problem of the influence of an inverter interfaced Distributed Generation (DG) on the speed and coordination of microgrid protection, an improved inverse-time microgrid current protection method based on composite fault compensation factor and a Beetle Antenna Search (BAS) algorithm is proposed. First, by analyzing the voltage distribution characteristics of the protection installation at the time of the fault and combining the characteristics of the measured impedance, a composite fault compensation factor is constructed. This solves the problem of long time delay caused by the short-circuit current changes in inverse-time overcurrent protection and improves the speed of protection. In addition, in order to solve the problem of microgrid protection coordination caused by factors such as DG access and changes in the operation mode of microgrids, the BAS algorithm is used to optimize the parameters of improved inverse-time overcurrent protection to ensure the coordination and cooperation of adjacent protections. Finally, a microgrid simulation model is built in DIgSILENT/PF software to verify the effectiveness of the improved method. The simulation results show that compared with the traditional inverse-time overcurrent protection, the improved protection method significantly improves the speed performance and meets the coordination requirements under different operating modes and fault conditions of the microgrid. This work is supported by National Natural Science Foundation of China (No. 51807114).