With the development of sensor array technology, more and more array technology is used in the fault diagnosis research of equipment. In this paper, based on the fault characterization and positioning problem in multirolling bearing diagnosis in equipment, a theoretical study on bearing fault location theory based on 2DMUSIC algorithm Ltype acoustic array is carried out. The main purpose of the research is to optimize the array parameters. According to the acoustic signal characteristics of the rolling bearing, the 2DMUSIC algorithm is used to simulate the dual source signal under the Ltype microphone array. Then, by changing the parameters of SNR, array spacing and array number, the optimal acoustic array parameters are determined. The simulation results show that, under the condition that the two signal sources have been determined, by optimizing array parameters, fault location resolution can be improved and sound source location system can be optimized. The research has a good theoretical guiding significance for the rapid positioning and realtime diagnosis technology of bearing faults in multibearing drive systems of rail locomotives.