Particle emission is one of the major problems during municipal solid waste (MSW) combustion. This study investigated the particle emission distribution in flue gas and the effect of three types of Si/Al-based additives (kaolin, chabazite, and clinoptilolite) on reducing the emissions of particulate matter with PM10 during MSW combustion. The yields of ultrafine particle PM0.3, fine particle PM0.3-2.5, and coarse particle PM2.5-10 at the combustion temperature of 1100 degrees C were 1.58, 1.92, and 8.76 mg/g of MSW (dry basis), respectively. At 5% additive mass ratio, clinoptilolite showed the best particle reduction of 36.57% for PM0.3. Si/Al-based additives reduced particulate emissions by enhancing the conversion of alkali chlorides and sulfates to alkali silicate or aluminosilicate, which improves the melting point of alkali salts. A high Si/Al ratio enhanced the conversion to alkali sulfate in the vapor of volatile alkali salt through the competitive reaction of alkali metal salts and silicon aluminum oxide and, thus, inhibited the condensation and nucleation of alkali salt vapors to form ultrafine particles. Additives with a low Si/Al ratio produced more Na/K-Si-Al mineral binder on the surface of fine particles through the aluminosilicate formation, which promoted the agglomeration and coalescence of fine particles and improved the emission of coarse particles. The specific surface area of coarse particles was related to the agglomeration and coalescence ability of the particles. Further, it was also evident that the chabazite additive significantly increased the proportion of Na and K elements in PM1-2.3 and PM2.5-10 particles because of its high specific surface area and adsorption capacity.