The Airbus 330-300 was scheduled to depart the country's Khon Kaen airport for Bangkok last night when the aircraft left the tarmac as the crew attempted a U-turn on the runway, causing its nose wheel to plough into the soft ground.
The two pilots of the flight TG047, 11 other crew members and 246 passengers were safe.
The damage to the aircraft was being assessed today, the Bangkok Post reported.
As the plane was unable to move, the airport had to close runway operations. The airport's single runway has no taxiways.
The incident is the latest to have affected Thai Airways, which is said to have suffered from a drop in tourism to Thailand in recent years because of political unrest.