Surface plasmon resonance (SPR) has tremendous application value in biosensing.The phase sensing of the resonant angle based on a prism structure exhibits higher sensitivity compared with the reflectivity sensing.Multi-channel real-time phase shift detection is a research highlight in SPR biosensing.An SPR phase detection system based on Kretschmann prism structure attenuated total reflection (ATR) single- path is proposed.The phase difference between P-polarized signal light and S-polarized reference light is controlled by a liquid crystal variable retarder (LCVR) to realize single-path interference.Fixed-point phase detection of two-dimensional surfaces is realized by an addressable micro-mirror array (MMA).The system can detect the phase shift information with a spatial resolution close to a single MMA pixel (7.64 μm horizontally/vertically or 10.8 μm diagonally).It is capable of realizing single-path,high-precision,multi-channel two-dimensional plasmon resonance phase shift detection,providing new experimental ideas for in-situ biosensors and phase imaging beyond diffraction limits.