South Bank's Brisbane sign, the colourful G20 installation that quickly became one of the city's most photographed landmarks, will be dismantled on Thursday.

But it will return, Brisbane City Council has said.

The riverside sign, put in place for last November's world leader's summit, was always intended as a temporary installation but soon after the meeting's conclusion, former Arts Minister Ian Walker announced work would get underway on a permanent replacement.

"It's become beloved of Queensland and a great symbol of this city and this state," he said.