In this study, we propose techniques for reducing aeroacoustic noise from gaps between cars and bogie sections. A microphone array placed adjacent to the main flow of the wind tunnel is used as a measurement device to improve the spatial resolution and the accuracy of identifying the noise sources. The results show that aeroacoustic sound sources at gaps between the cars are sufficiently weakened by rounding corners of cars, because the impact of impinging vortices at the corners is relieved and efficiency of acoustical radiation is reduced. Noise from the bogie sections is also reduced by installing side covers, slopes and round corners.