Yes, there is a tax, but only on goods, and it also depends on the total amount of goods carried.
If items bought in Hong Kong are brought back to the mainland, only items for personal use or gifts will be exempted from the 5,000 yuan per person. If they are sold, they will be taxed. Different tax rates apply to different types of goods. According to the relevant regulations, the general tax rate is between 10% and 50%. For indivisible single items, such as luxury watches, designer handbags, etc., the full amount is taxed.
According to the relevant requirements of the Customs: Chinese residents are allowed to bring their own personal belongings with a total value of up to 5,000 yuan (including 5,000 yuan) overseas and in Hong Kong, Macao and Taiwan, and are taxed according to the law.
Extended information:
Rules of Origin on Trade in Goods
Article 10: Goods imported under CEPA shall be transported directly from Hong Kong to mainland ports.
Article 11: When imported goods under CEPA are declared for customs clearance, the consignee shall take the initiative to declare to the Customs at the place of declaration that zero tariff is applicable to the goods and submit a valid certificate of origin in compliance with the provisions of the "Procedures for Issuance and Verification of Certificates of Origin" under CEPA. If the certificate of origin is verified by the Customs network to be correct, the Customs will allow the goods to be imported in accordance with zero tariff. If the certificate is confirmed to be invalid by the Customs verification, zero tariff shall not be applied.
Article XII of the declaration of the Customs on the authenticity of the certificate of origin of the content of doubt, the General Administration of Customs or its authorized Customs can be made through the General Administration of Customs to the Customs and Excise Department to assist in the verification of the request.
While waiting for the result of the verification by the Customs and Excise Department and confirmation of the certificate of origin concerned, the Customs and Excise Department of the place of declaration may first release the goods after levying a deposit equivalent to the duty payable in accordance with the duty rate applicable to the goods under non-Arrangement, and then go through the importation formalities and carry out the Customs statistics in accordance with the regulations.
After the completion of the verification by the Customs and Excise Department, the Customs and Excise Department of the place of declaration shall, according to the verification results, immediately handle the procedures for refunding the security deposit or the security deposit to be converted into import tariffs, and the Customs and Excise Department statistics shall be revised accordingly.
Baidu Encyclopedia - General Administration of Customs of the People's Republic of China