The theory and data processing method of the non-contact vibration testing system based on blade tip timing were introduced. The system was successfully applied in the blade vibration measurement on the first stage of rotor blades of a turbo-fan engine high pressure compressor

and the blade tip amplitudes and frequencies of the whole blades at resonance were obtained. The displacement-stress conversion ratio from blade tip magnitude to the critical points stress was calculated by the finite element analysis. The vibration character of the whole blades was obtained through the non-contact vibration testing system of the turbo-fan engine. As the thickness of prototypical blades was enlarged by the processing technology

the blades were resonated in the working speed caused by the engine order of 3

which led to the failure of the blades. The vibration character of remodelled blades is very well after promotion of processing technology.