According to the practical application of metro vehicles, the temperature properties of brake resistor in the outlet of B type vehicles were analyzed. Though the tests and numerical calculations, the temperature variation and temperature distribution characteristics of the brake resistor in the outlet during working were obtained, and its influence on the equipment safety below the metro vehicles board was analyzed. It was obtained that the equipment should tolerate 130℃ temperature at the range of 0.8~1 m of brake resistor outlet, which would provide the reference for the setup of the equipment.