The stability control of semi-coal rock soft rock roadway is an increasingly difficult problem in the current underground mining engineering. In order to solve this problem and reduce the cost of roadway maintenance, this paper takes the auxiliary transportation roadway in the north wing of Shanxi Qiyuan Coal Mine as the engineering background, and systematically studies the deformation mechanism and control technology of this kind of roadway by means of field measurement, laboratory test and numerical simulation. Through field investigation and drilling peep, the deformation and failure characteristics of the roadway were obtained, and its internal failure mechanism was analyzed. Through the indoor double shear test, the mechanical properties of the new anchor cable support structure and the ordinary anchor cable are compared and studied. The theoretical relationship between the stress of the new anchor cable and the deformation of the coal-rock structural plane in the weak part of the semi-coal-rock roadway is analyzed. A new support system of semi-coal-rock soft rock roadway with the new anchor cable as the core is proposed. The numerical simulation results show that the proposed support system can effectively control the deformation of semi-coal rock soft rock roadway, which can provide reference for similar projects.