Hong Kong Visa Required Documents:

Basic Document:-
Six months valid passport with old passport if have.
Visiting card.
Personal bank statement and Bank Solvency Certificate (Last 6 months)
NID Card copy
Passport Sized 1 Color Photo 
Tax Certificate

For Business Person:-
Renewal trade license copy with notary public ( English Translated )
Memorandum for limited company / Form XII / Company Certificate of corporate
Blank page of office pad.
Import/Export Certificate

For Job Holder:-
No objection certificate (NOC)
Salary certificate
Employee ID card copy
Provident fund certificate
BMDC certificate for Doctor
BAR council certificate for Advocate

For Student:-
Student ID card Photo copy.
Leave letter from School / College / University
Birth certificate (Only for Child & infant)

Others:-
Marriage certificate copy ( if spouse name not mentioned in the Passport )
Asset Valuation (Summary of Property, Bank Statement, Fixed Deposit and other Financial Documents).
Credit card copy + Statement ( if )