Abstract: Aiming at the problems of low efficiency and high labor intensity in manual inspection of tuyere middle sleeve inclination angle at the outlet of blast furnace, an inspection robot control system was designed to detect the inclination angle of the tuyere independently. Using STM32 single chip microcomputer as the controller, the temperature of outer wall of tuyere was collected by RS485 and RS232 circuits, and the related body information such as electric quantity, speed and distance was obtained. The magnetic conductivity sensor was used to detect magnetic nails buried in the ground to realize robot trajectory tracking and tuyere positioning. The data of the inspection robot and human-computer interaction interface were transmitted by the local area network covered by the site, and the online detection of tuyere inclination angle was accomplished by a random sample consensus (RANSAC) algorithm. The inspection robot embedded in the designed control system was placed on the tuyere platform of No. 1 blast furnace of Masteel for experimental test. The results show that in the process of adjusting the motion trajectory, the maximum distance of deviating from the centre of the magnetic nail trajectory is 10 mm, the offset is basically 0 when tracking stably, and the magnetic navigation effect is good. The robot’s detection accuracy is equivalent to that of the manual inspection, and the time efficiency is improved by 11%. The designed inspection robot control system can replace the manual detection of the inclination angle of the blast furnace tuyere.