Using polarization surface plasmon resonance (SPR) imaging as a sensor has the advantage of large throughput in detection, but its sensitivity has always been inferior to other SPR sensors. The high contrast of the two polarization parameters' images related to scattering determines the high sensitivity of this new polarization SPR imaging sensor. It provides a new direction for solving the issue of low sensitivity in polarization SPR imaging. The sensor system was optimized by numerical simulation, whilst the baseline noise and sensitivity of the system were obtained by saline solution and virus detection. When the reflective index of the NaCl solution is within the range of 1.3331 to 1.36, the average sensitivity can reach 9300 RIU-1, and the maximum sensitivity can reach 13000 RIU-1. Using this new polarization SPR imaging sensor, the H1N1 virus was differentiated, showing its promising application potential within the field of biomedicine.