Flight MH122 was travelling from Sydney to Kuala Lumpur on Thursday when it turned back not far from Broome, in Australia’s north-west.
The plane, carrying 224 people, landed safely at Alice Springs Airport at 17:48 local time (06:48 GMT).
Passengers said the plane had been shaking and making loud noises.
In a statement, Malaysia Airlines said the jet had been diverted for “technical reasons”. It did not elaborate on what they were.
Passenger Sanjeev Pandev said the plane appeared to have a problem about four hours into the flight.
“It was shaking and vibrating and the noise was getting louder and louder” he told the BBC.
“Some people were praying and people had tears in their eyes. It was a really terrifying moment.”
He said passengers were taken through emergency procedures by staff, some of whom appeared “nervous and terrified themselves”.