In order to obtain the resonance frequency of a new designed last-stage blade on marine turbine, the blade is excited by compressed air in the highspeed dynamic balance test bench. The signal of blade vibration is transferred to a signal analysis system by the telemetry transmitter and receiver when it is picked up by the inductive components, and the information of blade vibration is then obtained under multiple channels. The test data show that the "triple point" resonance speed is a modal family for pitch diameter number k=7 and k=8, and the range of resonance speed is beyond the working speed, respectively. Compared with the results from the numerical calculation and the testing, the tolerance of dynamic frequencies does not exceed 5% for pitch diameter number k=7&8. Numerical and experimental analysis prove that the blades in the operating speed are safe and reliable.