Regarding this question, AliExpress brand authorization can be purchased on the AliExpress official website. The specific steps are as follows:

1. Search for "Brand Authorization" or "Brand Authorization" on the AliExpress official website.

2. Filter out brand authorized merchants that meet the requirements.

3. Select a suitable brand authorized merchant and purchase the required authorization.

4. After purchase, complete the brand authorization procedures according to the authorization documents and guidelines provided by the merchant.

Please note that before purchasing AliExpress brand authorization, you need to first understand the relevant policies and requirements of brand authorization to ensure that you meet the authorization conditions. At the same time, you also need to communicate with the merchant before purchasing to confirm details such as the specific content and authorization period of the authorization.