To apply for a student visa for Hong Kong. His relatives living there can be his sponsor.
You should complete application form (ID 995A). The sponsor should complete application form (ID 995B). The application forms (ID 995A and ID 995B) can be obtained free of charge from the following offices:
Immigration Department Headquarters.
Immigration Branch Offices.
Overseas Chinese Diplomatic and Consular Missions.
The forms can also be downloaded from the Immigration Department's website.
In addtion, one of the applicant's parents should authorise the sponsor or his/her relative/friend in Hong Kong to be the guardian of the applicant. A consent letter duly signed by both the guardian and one of the applicant's parents should be produced. Other requirements are recent photograph, travel document/passport, A letter of acceptance from the educational institution, Photocopy of proof of the applicant's accommodation arrangement and Photocopy of proof of the applicant's financial support.