The Undanbi were an indigenous Australian tribe of southern Queensland.
The autonym Undanbi is formed from their word for 'man' (dan).
The Undanbi spoke a dialect mutually intelligible with that of the Jagera and Turrbal peoples, and it was apparently the dialect mastered by Tom Petrie.
The Undanbi occupied an estimated 900 square miles (2,300 km2) around the coastal strip along Coolum Beach and Moreton Bay, reaching down from Noosa Heads as far south as the estuary of the Brisbane River. It extended inland, around 10 miles, to the area of Pine River, and the Glasshouse Mountains. They also had a foothold on Bribie Island.
The western neighbours of the coastal Undanbi were the Dalla.
The Undanbi were divided into hordes
Physically, the Undanbi were known for their impressive builds, which marked them off from members of tribes like the Dalla, who were generally slighter.
The Brisbane horde of the Undanbi was said to have become extinct within a few decades of white settlement. Archibald Meston stated they had died off by 1860. Other testimony suggests a number were still alive, in 1883, at Mooloolaba).