In this study, gold nanoparticles (AuNPs) were grown on the surface of a metal‐organic framework (UiO‐66−NH2). The resulting AuNPs/UiO‐66−NH2 composite nanomaterials were further used for antibody immobilization on a microcantilever surface. By harnessing the robust signal processing capabilities of integrated circuits, a highly sensitive piezoelectric microcantilever sensor was constructed. The incorporation of nanomaterials resulted in enhanced antibodies immobilization amount, thereby improving the immunosensor‘s sensitivity. Under optimized experimental conditions, a promising linear correlation (R=0.993) was observed between the voltage output intensity of the microcantilever sensor and the logarithmic PCT concentration within a range of 0.1–50 ng/mL. The constructed microcantilever immunosensor based displayed several advantages such as simplicity, rapidity, high sensitivity, and low cost. Moreover, it potentially provided a novel approach to detect other biomolecules.