Simulation　study　of　the　failure　of　gearbox　system　using　virtual　prototype　technology　and　analysis　of　its　vibration　signal　is　a　foreword　topic　in　recent　years.　This　paper　established　a　rigid-flexible　coupling　model　of　gearbox　system　using　SolidWorks,　ANSYS　and　ADAMS.　Then,　make　simulation　under　the　following　three　conditions:　normal,　gear　fault　and　bearing　outer　ring　fault.　Next,　make　time　domain　and　frequency　domain　analysis　of　the　simulated　fault　signal　using　MATLAB.　Simulation　results　are　consistent　with　gear　vibration　mechanism　and　signal　modulation　theory,　which　verified　correctness　and　feasibility　of　virtual　prototype　technology　in　gearbox　fault　simulation.　Lay　foundation　for　gearbox　fault　diagnosis.　©　(2013)　Trans　Tech　Publications,　Switzerland.