Abstract: Acoustic emission (AE) is used to detect contacting fault of sliding bearings. The contacting fault was simulated on a sliding bearing bygradually reducingthe oil supply until no oil being supplied. AE signalswere recorded during the simulation for analysis. The results indicate that AE signals are sensitive and quick response to the changes in theworking condition of sliding bearings, good in anti-disturbance and easy to install, showing a prospect to be applied to fault diagnosis of sliding bearings.