Abstract: In order to prepare for the microcapsules of paper-making sheet casing solution and investigate their sustained-release effect in heat-not-burn (HNB) cigarettes, the volatile flavor components of the casing solution were analyzed, and the microcapsules were prepared by complex coagulation method, then their physical and chemical properties were characterized. Finally, the sustained-release effect of microcapsules in different sections of HNB cigarettes were studied. The results showed are as follows: ① There were 21 kinds of aroma volatile components in the papermaking casing solution, including 13 kinds of volatile components, indicating that the casing solution had strong volatility. ② The peak shape of infrared spectrum indicated the casing solution was successfully embedded and thermogravimetric curve showed that the temperature for rapid loss of casing solution in microcapsule was nearly 170 ℃ higher than that of the casing solution, because the wall material improves its thermal stability and reduces volatilization. ③ The average particle size of microcapsules was 240 nm, the embedding rate was 34.11%, and the moisture content after 7 days was 9.37%. The appearance is light golden yellow powder. According to the scanning electron microscope, its structure was dense, and the surface of the capsule wall was relatively smooth and approximately ellipsoidal. ④ The results of flavoring and sustained-release experiment showed that the effect of microcapsule added in tobacco section and the amount of 0.015 g was optimal. It not only increased the amount of aroma, the sustained-release effect was obvious, but also significantly reduced the irritation, improved the strength, and the aftertaste returned to sweet, which provided a theoretical basis for the application of microcapsule technology in HNB cigarettes.