For the demands of high speed and efficiency of on-line measurement of roundness in machining industry, a kind of High-speed roundness measurement system based on the piezoelectric displacement transducer that used the Polyvinylidene fluoride film was developed. It can achieve the goal of high-speed roundness measurement by combining with charge amplifier and taking advantages of transducer such as the high frequency, sensitivity and signal-to-noise ratio. From the experiment study, known that the measuring frequency response of the PVDF transducer is over 1200Hz and the resonance peak is about 3000Hz. It has solved the problem of distortion measurement that caused by the inductive transducer in high-speed measurement. The results showed that this system roundness error measurement precision can reach less than 1μm. Repeated measurements show that the measurement results of the system has high reproducibility and reliability.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.