The NT Fire and Rescue Service received a report of a structure fire on Timpson Court in Gray just before 3am.
Upon arriving at the unit complex, crews found a duplex fully engulfed in flames.
Firefighters conducted a search of the premises but found no occupants inside.
Crews worked quickly to contain the fire and had extinguished it shortly before 4am.
No injuries have been reported.
NT Police and St John NT were also in attendance.
A fire investigator and Police will visit the scene today to determine the cause of the blaze.
Anyone with information is encouraged to contact NT Police 131 444. Anonymous reports can be made through Crime Stoppers on 1800 333 000.
Quotes from NT Fire and Rescue Service Territory Duty Officer, Eric Koomen:
"We encourage anyone with information regarding the fire to please contact police.
"Thank you to our crews and their fast response in containing and extinguishing the fire and ensuring it did not spread to any of the surrounding units."
