Councillor George Ryan died, aged 51, after a suspected heart attack.
The father-of-three passed away suddenly on Saturday.
Councillor Ryan was elected to Glasgow City Council in 1995 and represented the Shettleston ward.
He was praised for his work within the city council, including helping to introduce the Living Wage and Commonwealth Apprenticeship Initiative.
Leader of Glasgow City Council, Councillor Gordon Matheson, today led tributes to Councillor Ryan.
He said: "This is devastating and unexpected news. We are still trying to take it in.
"I can only imagine how his family, especially his wife Linda, and his children, Christoper, Deborah and Sophie, are feeling.
"Our thoughts and our prayers are with them at this awful time."
During his political career, Councillor Ryan held a number of high-profile roles, including executive member for business and the economy.
Councillor Matheson added: "George was a highly respected and experienced Labour councillor and trade union activist, as well as holding down a professional career in health and safety.
"He was astute, warm and popular, and a big and influencial figure in the City Chambers.
"His political background made him ideally suited to laterally lead on personnel matters within the council.
"He held many senior positions over the years, including being in charge of economic development at the time we introduced the Living Wage and Commonwealth Apprenticeship Initiative.
"These projects demonstrated his socialist values.
"The people of Shettleston have lost a powerful champion and the city has lost a fighter for social justice."