He said the new building was necessary to serve rising passenger numbers and reduce congestion at the existing terminal.
The airport currently serves 192 flights a week, up from 170 flights in the summer of 2012. It hosts 34 airlines with regular flight schedules and another six airlines for chartered flights.
The new terminal building was built at a cost of more than 100 million baht. Passengers will be able to check-in at the terminal. A bus service will transfer passengers in between the two terminals.Terminal X will have the capacity to serve up to five million passengers a year or around 4,000 passengers per hour.
Mr Maitree said the new terminal will officially open to customers on Feb 5, but the building will be open for other purposes from Feb 1.
Phuket International Airport is meanwhile in the process of building five additional aircraft decks. Once construction is complete the airport will be able to accept 20 aircraft arrivals and departures at the same time.
The airport is expected to serve around 10.5 million passengers in 2013.