Cosatu said George who grew up in the streets of the Cape Flats, became a key leader in the trade union movement and other sectors of society.
The trade union federation said that George led from the front during his time as a leader in the trade union movement.
It added that George had played an instrumental role in shaping the labour market arena after the 1994 elections, adding that he never shied away from speaking his mind.
George was the General Secretary of the Federation of Unions of South Africa (Fedusa) for many years.
“Comrade Dennis George was a major figure in the trade union movement and was deeply respected by all. He was not afraid to express and stand by his views and fearlessly led his members to battle exploitative employers.
“He was a formidable trade unionist who contributed immensely to building and shaping the post-1994 labour market landscape. He believed in education and that the nation should invest in skills development to reduce unemployment.
“ He believed in life education and earned a PHD well into his years as a General Secretary, with his thesis focusing on how social dialogue can be used to improve the lives of the working class.
“He was a reliable partner at Nedlac, endeavoured to work closely with Cosatu and other trade union federations, always fostered worker unity, and believed in building bridges with other social partners to fix South Africa’s problems,” said Cosatu.
George was also the founding director of African Quartz. He also served on the board of Ayo Technology Solutions.