Real estate firm CBRE is spruiking the vacant block on Braybrooke Street as a prime location for a mixed-use development, given its proximity to Canberra Stadium, the University of Canberra and Calvary Hospital.

Agent Adrian Woolgar said some of the biggest names in Canberra's property market had already expressed interested in the 3,161 square site, which has approval for a 118-room hotel and serviced apartments, and includes space for a carpark.

The sale comes three years after prominent developer Nik Bulum and architect Nathan Judd lodged plans for a $19.75 million development on the site.

The project was to include two separate, but joined buildings. One was set to feature a six-storey hotel and function room; the other a five-storey block containing 31 apartments.

Plans were approved in February 2016, but the project never got off the ground. The site was subsequently sold to Turner-based Maxon Property Group, Mr Woolgar said.

He said the developer had originally planned to push ahead with a redevelopment of the site, before strong recent land sales promoted it to consider putting the site back on the market.

Mr Woolgar expected the site would fetch between $5.5 and $6.5 million, and draw interest from interstate developers, particularly from Sydney.

"Everyone knows there is lots of apartments in Belconnen, but Bruce is a little bit on its own and there is not a lot of stock there," Mr Woolgar said.

"It's an established area and the demographic is of people on a good income and there's lots of families, too."

Mr Woolgar said the opportunity would be particularly enticing to developers because it did not involve government-owned land, which subjects buyers to certain development conditions.

Expressions of interest for the site close at 4pm on March 7.