Direct Transit in Hong Kong International Airport (during 15 hours of transit time)

Tuan, you should apply for a Hong Kong visa before your travel. First, get the following things prepared: application form ID 1003A, recent photograph affixed on the application form, photocopy of your passpor, photocopy your financial standing proof, e.g. bank statements, savings accounts passbooks, tax receipts, etc. and proof of employment (if any), e.g. company leave letter, salary slips, etc., photocopy of flight tickets, photocopy of proof of the proposed visit in Vietnam after visiting Hong Kong, itinerary, etc.. Then mail the documents to HK Immigration Department.

Thanks Tina for the reply. It's an ideal case that I will have a Hong Kong entry permit. However, I am flying in 2 days, so getting one is not an option for me. I am wondering if I can get a 24 hour free transit, which is described in the section 2 (For Direct Transit) above.

Sorry, the contents in section 2 are about direct transit policy in mainland China rather than in HK. So you still need the HK entry permit. But I heard that if you take the plane of some airline, you will not be required for the entry permit for direct transit. You can try to find such an airline.