Northern Territory police say a would-be burglar has been electrocuted while breaking into an outback petrol station.

Duty superintendent Michael Murphy says the owner of the Jabiru petrol station found the 24-year-old man dead inside the roof about 11pm Sunday.

He says the man's body was found hanging and entangled in the cables.

"It appears the male has entered through the roof space into the ceiling cavity, obviously activated the alarm and I believe at this stage has either panicked or he's tried to terminate the alarm by cutting cables with a pair of secateurs," he said.

"He's inadvertently grabbed a live power cable, cut that and obviously... had fatal injuries from electrocution."

He says it is the second time in a week that someone in the Northern Territory has been electrocuted by roof cabling.

"We've [also] seen the tragedy of the death of a 23-year-old man at Palmerston, who died from what appears to be electrocution as well," he said.

"Have qualified people deal with electrical cables, anything that requires adequate training - get your qualified people to engage in that sort of thing, don't do it yourself because there's inherent dangers with it."