Kier has reached a mutual agreement with the Glasgow School of Art to cancel its contract to refurbish the Mackintosh Building.
A joint statement from both parties said they had agreed that there was no way the current contract could be fulfilled following the fire on 15 June that devastated the structure.
Kier signed a £25m contract in June 2016 to restore the building after it was badly damaged by a fire in May 2014.
The restoration was due to be completed next January, but a fire that broke out on 15 June destroyed much of the building.
Kier has defended the fire safety strategy it employed at the site, which it said included a 24-hour patrol along with heat and smoke detection systems.
An investigation into the cause of the fire is under way.
A survey by Glasgow council this week found that some walls were at risk of sudden collapse.
Demolition of some of these areas will begin in the next few days.