Abstract: In order to exactly determine the fault of the ventilator and realize the early warning of it,the warning principle of the ventilator failure is proposed.The fault early warning software based on the informa- tion fusion technology is developed using VC++6.0 combined with Matcom 4.5.Information fusion tech- nology and BP neural networks and evidence theory are adopted in the software,in which non-linearity map- ping between the fault style and the diagnostic frequency is accomplished by the BP neural network and multi- channels signal fusing and analyzing is carried out using the theory of evidence.Data acquisition and conclu- sion return are realized by using the OPC mode communication between the King View running system and the developed software.