Abstract: For the contamination problem of micro-particles on glass surface, the cleaning threshold of pulsed laser and its cleaning effect on particle contaminants are studied in this paper. The particle adsorption and deformation model was used to calculate the particle adsorption force. The relationship between thermal stress and laser energy density was analyzed, and the cleaning conditions and theoretical thresholds for particle contaminants were obtained. The cleaning effect of forward irradiation and back irradiation of particles on glass surface were compared in experiments, and the effect of parameters such as power density, scanning speed and cleaning times on the cleaning rate were studied. The results show that the back irradiation cleaning of large particles can be removed, and forward irradiation cleaning of small particles is more effective. The experiments of single-factor and three-factor show that the laser power density has a greater impact on the cleaning rate than the scanning speed, and the laser cleaning times have little impact.a greater impact on the cleaning rate than the scanning speed, and the laser cleaning times have little impact.