Abstract: In order to investigate the influences of tobacco powders of different particle sizes on the quality of tobacco materials for electrically heated tobacco products (eHTPs), slurry processed reconstituted tobacco was prepared by using tobacco powders of different particle sizes (180-380 mesh, 39-80 μm) on a home-made slurry reconstitution experimental platform. The surface microstructure and thermo-gravimetric characteristics of the prepared reconstituted tobacco were characterized by scanning electron microscope and simultaneous thermal analyzer respectively. The amount of smoke released from eHTPs with tobacco materials made from tobacco powder of different particle sizes was qualitatively analyzed by an e-cigarette smoke analyzer. The results showed that: 1) When the tobacco powder particle size was larger than 280 mesh(52 μm), the reconstituted tobacco featured a uniform powder distribution and compact microstructure. 2) The thermal weight loss characteristics of the reconstituted tobacco was analyzed within the range of 0 to 600 ℃, and the major weight loss stage was from 40 to 370 ℃, reaching greater than 50%. 3) During heating, the amount of smoke released closely negatively correlated to the tobacco powder particle size, namely the amount increased with the decrease of the particle size.