In this paper, aiming at the problems of large braking impact and easy tipping off of the traditional endless rope claw brake tractor, taking the SQ-60/75P endless rope tractor in use of Shanxi Xinjing Coal Mining Co., Ltd.as the research object, a magnetic suction brake mechanism is designed to solve the problem of unstable braking of the endless rope tractor. In this paper, the functional design of the magnetic suction mechanism of the endless rope tractor is carried out, the working principle of the system is expounded, and the design idea of the overall structure is determined according to the functional principle. On this basis, the detailed structure of the magnetic attraction mechanism of the endless rope tractor is designed. The magnetic attraction of the permanent magnet component and the braking force of the magnetic attraction mechanism are theoretically calculated, and the performance parameters of the friction material are determined. The three-dimensional geometric model of the magnetic swing arm mechanism, the swing arm support plate, the wire rope support block, the tension spring, the car body support and other components is established, and the normal state, the critical state, the release state and the braking state of the magnetic brake mechanism are analyzed. The detailed working conditions and the design intent of the detailed structure. The braking response time of the magnetic attraction mechanism of the endless rope tractor is theoretically calculated. The field test shows that the braking response time of the magnetic suction mechanism fully meets the requirements of ' Coal Mine Safety Regulations ' and ' MT/T590-1996 '. Compared with the traditional endless rope tractor, it has great advantages in stability, safety and reliability.