The power of oil of Turbine's hydraulic system in a power plant was provided by gear pumps,and fault occurred in the gear pumps would affect Turbines safety operation.Therefore,Peak Vue technology and related Emerson CSI 2130 vibration analysis machine were used to diagnose gear pump's fault.Practice proves that the Peak Vue technology is good at telling the fine fault signal apart from noise signals,and clearly estimating the fault signal of gears and bearings with high accuracy and reliability.