Books with ISBN in Hong Kong belong to Hong Kong commodities. If it is sold in the mainland, the current policy requires qualified book companies to go through import and export procedures, import and record. For example, Hong Kong's Phoenix Weekly and Forbes can now be publicly distributed in the Mainland.

At present, some small bookstores in the mainland also sell books of ISBN in Hong Kong, which depends on the business philosophy of bookstores and the recognition of books in the local market, and has nothing to do with policies.