It is illegal to sell masks privately, because masks are also medical devices. According to national regulations, if you want to operate, you must have relevant qualifications and obtain a business license. Therefore, ordinary people are not allowed to sell it privately. If the mask sold is genuine and the quality meets the standard, it may be suspected of illegal business operation. Article 225 of the Criminal Law

Legal objectivity:

Criminal law of the people's Republic of China

Article 225

Whoever, in violation of state regulations, commits one of the following illegal business operations and disrupts the market order, if the circumstances are serious, shall be sentenced to fixed-term imprisonment of not more than five years or criminal detention, and shall also, or shall only, be fined not less than one time but not more than five times the illegal income;

If the circumstances are especially serious, he shall be sentenced to fixed-term imprisonment of not less than five years, and shall also be fined not less than one time but not more than five times for illegal gains or confiscation of property:

(a) operating a franchise or monopoly commodity or other commodities whose operation is restricted by laws and administrative regulations without permission;

(2) buying and selling import and export licenses, import and export certificates of origin and other business licenses or approval documents stipulated by laws and administrative regulations;

(three) without the approval of the relevant competent departments of the state, illegally engaged in securities, futures, insurance business, or illegally engaged in fund payment and settlement business;

(four) other illegal business activities that seriously disrupt the market order.