The regulation strategy for E-cigarettes is not unified all over the world. Except for some countries that either completely prohibit E-cigarettes or have not yet declared, the other countries variously regard it as tobacco, a pharmaceutical product, or as an ordinary consumer product (see Table 1) . The following part will introduce the E-cigarette regulation strategy in different countries. Some countries adopt a “classification regulation” strategy, classifying the E-cigarettes according to the existence of nicotine or tobacco extract in e-liquid or, the content and concentration of nicotine. Different types of E-cigarettes comply with different control policies. The classification standards of E-cigarettes in different countries are quite different. Generally, E-cigarettes can be classified into one of three categories: tobacco, pharmaceutical products, or ordinary consumer goods.