The utility model provides a railway tunnel boundary limit dynamic inspection system based on laser scanning distance measurement appearance. The system includes many laser scanning distance measurement appearance and host computer, many laser scanning distance measurement appearance are installed respectively in the inside sectional different positions of same railway tunnel of railway tunnel gauging verification car automobile body, each laser scanning distance measurement appearance passes through ethernet and upper computer connection. Acquire the sectional different position sigual of same railway tunnel in real time, according to the central distance to railway tunnel section measuring point of laser scanning distance measurement appearance, the rail plane central point that converts out to the distance of this measuring point, storage rail plane central point arrives the distance and the angle of the different measuring points of same railway tunnel section, generate the sectional formation of image of each railway tunnel. The laser scanning distance measurement appearance detects the different positions of the same section of tunnel hole wall simultaneously, guarantees to cover full tunnel dong bi, the laser beam that the laser scanning distance measurement appearance is launched just can cover the boundary limit measuring range of tunnel profile 360.