The invention relates to a control system and method, in particular to a parallel motion control system and method for a rock drill, and belongs to the technical field of engineering. The system comprises a first multi-way control valve group, a first hydraulically controlled directional valve group, a first large oil cylinder, a first large oil cylinder cartridge balancing valve group, a first small oil cylinder, a first small oil cylinder cartridge balancing valve group, a second multi-way control valve group, a second hydraulically controlled directional valve group, a second large oil cylinder, a second large oil cylinder cartridge balancing valve group, a second small oil cylinder and a second small oil cylinder cartridge balancing valve group. Thus, the system and the method have the advantages as follows: 1, leakage of series connection pipelines can be avoided; 2, air in the series connection pipelines can be exhausted with motions of the oil cylinders and cannot be accumulated, and parallel motions of the rock drill is easier to control; 3, the parallel motions of the rock drill can be controlled stably.