In order to evaluate the safety of heat-not-burn tobacco sheets during suction and establish the theoretical basis for adding flavors and fragrances in the process of heat-non-burn cigarettes, the mainstream heating-not-burn tobacco samples from domestic and foreign markets were comprehensively analyzed from physical and chemical indicators, thermogravimetric analysis and pyrolysis analysis. The results showed that: the content of hot water extract was 49.98%~66.59%, which difference was not remarkable. And the content of total sugar was 6.62%~28.93%, the content of reducing sugar was 4.79%~22.30%, the content of total alkaloid was 0.14%~1.13%, the content of total nitrogen was 0.31%~2.50%, and the content of ash was 4.21%~11.10%. The temperature range of TG is 200~500 ℃, and the weight loss rate is 2.23%/min~12.33%/min. The final biochar yield rangeed from 4.89% to 11.96%, and the weight loss rate and final biochar yield were different. The main aroma components produced by pyrolysis of the heate-not-burn sheets included 2-methoxy-4-vinyl phenol, d-limonene, glycerol and n-hexadecanoic acid. The main harmful components produced by pyrolysis included butane, acetic acid, furfural and phenol. There were some differences in aroma components and harmful components in different slices.