Jan Roos, was a Flemish artist who, after training in Antwerp, mainly worked in Italy where he was called Giovanni Rosa. He was known for his still life paintings of flowers and vegetables, mythological and religious scenes and portraits. His style of still life painting had an important influence on the art of the local painters of the Genoese school.

Jan Roos was the son of a merchant. He studied painting with Jan de Wael from 1605. In 1610 he joined the workshop of Frans Snyders, the important still life and animal painter who had recently returned from Italy. There he acquired a mastery in painting still lifes and animals.

In 1614, Roos travelled to Genoa and then on to Rome, where he stayed for almost two years. With the intention of returning to Antwerp, he traveled back in 1616 via Genoa. Given the high demand for his work in Genoa he decided not to continue his return journey and so he stayed in Genoa for the remainder of his life.

He married in Genoa with Benedetta Castagneto. He opened a workshop that became the busiest of the Flemish Genoese colony. His brother in law who is known only by his Italian name Giacomo Legi, but who was originally from Flanders, was a student in his workshop. It is possible that Roos was encouraged to seek his luck in Italy following in the steps of his first master Jan de Wael's two sons, Lucas (1591–1661) and Cornelis (1592–1667). Genoa was an attractive destination for artists since the competition between artists was less intense there than in Rome, Florence and Venice, while at the same time Genua was a wealthy city with a large number of potential customers and collectors.

Jan Roos achieved considerable success as demonstrated by the presence of his name in a number of contemporary inventories. The artist remained in Genoa until his death in 1638.