Flight Tan Son Nhat International Airport departs from Ho Chi Minh City Tan Son Nhat International Airport at 11:25 and arrives at Hong Kong Hong Kong International Airport at 15:15.
The flighttime is about 2h 50m. The distance travelled ("as the bird flies"): 917 Km. So the average speed is roughly 324 Km.
There is an 1 hour time difference between Ho Chi Minh City and Hong Kong