The linear light beam scanned surface plasma resonant imaging light intensity detection method and system belongs to the field of biological detection technology. In the incident optical path, one vibrating mirror driven with one vibration and oscillation driver is set to alter the incident angle to the sensing surface and to complete linear light beam scanning. When the biomolecules in the surface of the protein chip act mutually, the vibration mirror reflected light radiates to the sensing surface in constantly changed angle to excite the surface plasma on the protein chip to resonate constantly, so as to obtain corresponding light intensity signal with the photoelectronic detector. Once the vibration mirror frequency is fixed, the detector signal is recorded to complete the detection. The present invention has simple system structure, high sensitivity, high precision and capacity of multichannel detection.