Abstract: According to the system composition of the drilling rig for the gas drainage in underground mine, an integrated model of the virtual prototype machine for the drilling rig was established, including the geometry CAD model, virtual assembled model, structure strength model, hydraulic feature model and multi-body dynamic model.A relevant integrated design process of the virtual prototype machine was provided and could form a virtual development environment, including two modules of t he digitalized modeling and simulation.Based on a ZDY6000LD (A) directional drilling rig as an example, a virtual design of the drilling rig was conducted.The stability a nd firm features of the drilling rig were analyzed and the multi-body and hydraulics combined simulation was conducted on the performances of the directional drilling.B ased on the technology modelling of the virtual prototype machine, the ZDY6000LD (A) directional drilling rig could inspect the product performances at the initial desig n period and could provide the references to the prototype test.The drilling rig had been applied to the shenhua Group and other coal mines and completed a horizontal directional long borehole with a depth of 1 212 m.