Guido Molinari was born Benito Claudio Dino Guy Molinari in Montréal. His father Charles was the noted musical director and founder of the Montreal Symphony. Molinari studied briefly at the School of Design at the Montreal Museum of Fine Arts (1950-51), and began making drawings and paintings combining automatic methods with a disciplined approach. He was a leader in the development of a rigorous colour abstraction in Montréal.
Vertical, hard-edged bands of colour characterized his paintings in the 1960s. Pictorial space in these works was created by the spectator’s perception of the shifting and mixing of the colours. Later, colour in his work was reduced to very dark values, and rather than narrow bands the paintings were divided into 2 to 5 large vertical sections. In 1956 Molinari was a founding member of the Association des artistes non-figuratifs de Montréal. He practised abstraction in New York and was honoured with a Guggenheim Fellowship in 1967. He exhibited at the Biennale in Venice in 1968, where he was awarded the David E. Bright Foundation prize. In 1971 he was made an Officer of the Order of Canada. In 1977 he participated in the Paris Biennale, and in 1980 he was awarded the Paul-Émile Borduas Prize by the Québec government.
Molinari, who taught at Concordia University until 1997, exerted a powerful influence on younger artists through his teaching, theoretical writing, and his opinions, which were firmly held and strongly stated. The exhibition Guido Molinari: 1951-1961, Peintures en noir et blanc was organized by the Vancouver Art Gallery in 1989 and toured the country. Guido Molinari died in Montréal on February 21, 2004 at age 71.