A piezoelectric immunosensor was developed for the detection of p16INK4a, a protein that is expressed in liquid-based cervical cytology specimens and has been proved to be linked cervical cancer. Mouse polyclonal antibody against p16INK4a was bound onto the piezoelectric crystal surface in an ordered orientation using protein A. The antibody on the crystal could specifically adsorb p16INK4a and changes in the mass of the crystal would led to frequency shift. The supernatants from different clinical samples, including various cervical lesions, containing different concentration of p16INK4a were used for testing. Under the optimized conditions, the frequency shifts were linearly dependent on the antigen concentration in the range of 50–1200ngmL−1. The device showed a short analysis time (less than 30min), good reproducibility (could be reused six times without any detectable loss of activity), stability (the immunosensor was stable for more than eight weeks when stored over silica gel blue at 4°C), and specificity. Attempts have been made to use the sensor for the initial screening for cervical lesion in cervical cytology specimen, and the relationship between cytologic and histologic findings, p16INK4a expression in various cervical lesions, including carcinoma been investigated.