In Taiwan, the regulations on tobacco products packaging in the Tobacco Hazards Prevention Act mainly provide for the regulation on packaging label or advertising method, in case of its violation the violator is punished by fine and publicized its name and the fact of violation. These regulations have certain impact on freedom of expression, freedom of business and free choice on consuming products, which raises doubts on their constitutionality. Moreover, discussions on the plain packaging regulation on tobacco products are recently subject of international attention. Whether the Taiwanese Health Authorities may enforce stricter packaging regulation relates to its compatibility with requirements of the rule-of-law principles. In view of experiences in Japan, the United States and Australia, this study will examine the constitutionality and legality of the current regulations on tobacco products packaging.