1. power of attorney for trademark agency: a power of attorney stamped with the applicant's seal is required. Applicants from outside the mainland who want to apply for trademark renewal in China must entrust an agent. 2. Trademark renewal application: If Bajie Intellectual Property is entrusted to apply for trademark renewal, Bajie Intellectual Property will make it. 3. Prepare the required materials: 4. Copy of trademark certificate; 5.6. A copy of the applicant's main qualification certificate. A copy of the certificate that the trademark has been changed and other matters 7. Submit an application to the Trademark Office. Substantive examination of the Trademark Office. Issue a trademark renewal approval certificate. Although the trademark can be used within ten years after registration, it will enter the extension period once it expires. If the original trademark owner wants to continue to use the trademark, it is undoubtedly necessary to ask for an extension after paying a certain fee during the extension period. According to the law, the extension period is generally about six months.