The components of the provided E-cigs liquids were analyzed by solvent extraction-gas chromatography/mass spectro-metry and headspace GC/MS (HS-GC/MS). Under the standard suction (ISO) condition, the atomization behavior of E-cigs was studied. The results indicated: ① The content of PG, glycerol, and nicotine in E-cigs liquid was higher than the other components. The other components were mainly tobacco essences and extracts. ② The component of PG in mainstream cigarette aerosol was highest, which up to 588.5 mg/g. The glycerol content was up to 290.2 mg/g, and the nicotine content was 10.4 mg/g. ③ E-cigs liquid was atomized and trapped by Cambridge pad, and the mainstream cigarette aerosol was mainly particulate matter. The average atomizing efficiency was 11.99%, and the efficiency in every puffing smoke was 0.30% under the standard puff conditions. The pretreatment process of static headspace analysis is simple and convenient, and it has advantages in qualitative analysis. However, pyrolysis will lead to the generation of aldehydes and ketones with small amounts of molecular weight. Therefore, the use of solvent extraction and GC-MS is more suitable for quantitative analysis.