Queensland police say they are speaking to a man who was at a unit, south of Brisbane, where officers found a woman shot dead last night.

It is believed he lived with the 26-year-old victim at the Springwood home in Logan.

The man is assisting police with their inquiries.

Detective Superintendent David Hutchinson says a number of guns were also found in the unit.

"The information that we have at the moment is that only one weapon was fired," he said.

"We have located a number of weapons at the house and those weapons will be tested to determine if it was the weapon used."