A high sensitivity sensor based on anapole mode is designed， which consists of a metal reflector， a SiO2 thin film and a slotted silicon disk. The anapole mode in silicon nanoarray is used to excite the metal reflector layer to generate plasma resonance， and sharp resonance peaks can be generated in the periodic nanostructures through mode matching and coupling between adjacent structures. The structure is simulated and analyzed by finite difference time domain method， and the influence of different parameters on the sensitivity of the sensor is studied. The simulation results show that the nanostructures can significantly enhance the local electric field and reduce the energy absorption rate. The spin-orbital angular momentum conversion around nanostructures can be realized by using circularly polarized light， which is beneficial to the sensing of biomolecules such as neurotransmitters.