The airline says the incident today involved a SAAB 340B turboprop chartered by Siam General Aviation Company Ltd., which is known as Nok Mini.
The flight left the northern city of Chiang Mai and was landing at Undon Thani airport at the time.
Nok Air blamed "a glitch in the engine" but gave no other details. The airline says the plane is not blocking other flights and will be inspected.