Jean-Guy Desrosiers was born in Sorel, Quebec in 1934 and moved to Quebec City early in his life, where the city became a lasting source of inspiration for his work. He studied Fine Arts at the École Technique in Ottawa and the Academy of Fine Arts in Quebec, and later taught fine arts in Quebec City. Despite his formal education, Desrosiers considers himself a self-taught painter. He is a member of the Charlesbourg Artistic Society and the Monte-Carlo International Arts Guild.
Desrosiers has worked as a painter for over fifty years, primarily using oil paints to create landscapes, portraits, still lifes, and occasional abstract works. His artistic practice involves painting outdoors in locations such as old Quebec, seaside areas, and the Charlevoix region, where he creates sketches that complement his studio work. He maintains a disciplined routine, often rising before dawn to paint and working six days a week. His approach to composition includes working paintings from multiple angles, sometimes turning canvases upside down to ensure they work from any orientation.
His paintings typically feature rural Quebec scenes and Quebec City subjects, rendered in warm, earthy tones with what has been described as a sentimental and playful perspective. Desrosiers also paints Maritime themes including boats and coastal villages. His work is characterized by its narrative quality, as he enjoys telling stories through each landscape or still life. The artist's paintings reflect his optimistic outlook and have been exhibited throughout Canada, the United States, and Europe.