The locality takes its name from the mountain of the same name which occupies most of the western side of the locality, is part of the Mount Barney National Park and is undeveloped bushland. Farm land lies in a valley of the Logan River in the eastern part of the locality which separates the mountain Mount Barney from Mount Gillies in the very east of the locality. There are crops and grazing in the valley.[3]
In the 2016 census, Mount Barney had a population of 22 people. The locality contains 23 households, in which 50.0% of the population are males and 50.0% of the population are females with a median age of 31, 7 years below the national average. The average weekly household income is $0, $1,438 below the national average.[6]
In the 2021 census, Mount Barney had a population of 46 people.[1]