Local television images showed ambulances on the tarmac at Hong Kong's airport taking away the injured, who were on a South African Airways jet from Johannesburg which landed at around 12:30 pm (0430 GMT).
Hong Kong airport authorities said they were notified by the plane's captain at 11:00 am that they would need help from emergency services when they came into land.
"There was a plane that flew in from South Africa that saw multiple passengers injured when it encountered turbulence," a police spokeswoman said.
South African Airways could not immediately comment when contacted by AFP but an online flight tracking system said the plane was a four-engined Airbus A340-300.
Authorities could not confirm the total number of passengers on board.
South African Airways is the country's national carrier and one of the continent's leading airlines.