Based on kinematics analysis of dual-arm drill rig, operation ability and ideal position of dual-arm drill rig were analyzed, collision detection methods of dual-arm drill rig between the arms and between the arms and roadway were studied, and an automatic drilling method for dual-arim drill rig was put forward. A simulation experiment was carried out in Matlab. The experimental result shows that the method can make the arms of dirll rig arrive the ideal position and realize automatic drilling, which lays a foundation for further research on trajectory planning of the arms of dual-arm drill rig and automatic drilling.