Yeti the police dog has led Northern Territory police to 20kg of cannabis stashed in a man's car.

NT Police say a 42-year-old driver was pulled over at a checkpoint on the Stuart Highway near Adelaide River on Saturday evening, when police noticed a strong odour coming from the vehicle.

Their black labrador drug detector promptly led them to three suitcases in the car, allegedly containing 20kg of cannabis divided into 44 cryovac bags.

The man has been charged with possessing and supplying a commercial quantity of cannabis, and will appear in Darwin Magistrates Court on Monday.