The Scottish broadcaster and author said it has been “the greatest honour” to help with governing the institution but that it is time for a “fresh, energetic, and long-term committed person” to take over the role.
The world-renowned Charles Rennie Mackintosh-designed Mackintosh Building at the art school was extensively damaged by a blaze in June 2018 while it was undergoing a £35 million restoration following a previous fire in May 2014.
Ms Gray will stand down as chairwoman of the Board of Governors at the end of this month.
She said: “The privilege of assisting with the governance of this magnificent institution, my alma mater, has been the greatest honour.
“With the board having reached a number of key milestones, including successfully recruiting and appointing a highly qualified and experienced new director, assisting the Scottish Fire and Rescue Service with their investigation into the 2018 fire, setting in motion the process to decide the future of the Mackintosh Building, and supporting our hard-working senior management and staff in negotiating the obstacles created by the terrible pandemic, I feel that we are now in a considerably more positive place.
“Having given this a great deal of consideration I believe that as I enter the final year of my third term as chair the time has come to introduce a fresh, energetic, and long-term committed person to the role who can take the GSA forward to the next exciting phase.”
Glasgow School of Art (GSA) said it will announce an interim chairperson as soon as possible, and begin the process for election of a new one in the coming weeks.
A GSA spokeswoman said: “Over the past eight years Muriel has been a committed and enthusiastic chair, and a staunch advocate for the value of creative education.
“While her tireless support for the school will be hugely missed, we are sure that she will remain a much-loved supporter of our students, graduates and staff.”
In June the Scottish Fire and Rescue Service said that the investigation into the 2018 fire is expected to be completed by the end of 2021.