The analysis of the erosion characteristics of ceramic channel walls during the operation of Hall thruster is of great significance to evaluate the performance and lifespan of Hall thruster. Traditional erosion evaluation methods mainly rely on measuring the depth of erosion, which is time-consuming and unable to provide real-time online monitoring capabilities and multi-condition monitoring. Therefore, this paper uses non-invasive and in-situ online optical emission spectroscopy to monitor the erosion during the operation of the Hall thruster, and successfully detects the boron atom signal. Then, advanced actinometry method is used to calculate the boron atom reduced concentration under different working conditions based on the ratio of xenon atomic spectral line to boron atomic spectral line and the electron temperature calculated by xenon atomic collision radiation model. The results indicate that the reduced concentration of boron increases with the increase of mass flow rate and voltage, and the influence of magnetic field intensity on the boron atom reduced concentration is complex and requires further investigation. The use of emission spectroscopy and advanced photometry enables real-time and in-situ efficient assessment of erosion characteristics of aerospace equipment under different operating conditions, provideing guidance for the design and lifetime optimization of thrusters in key applications such as deep space exploration and gravitational wave detection.