van Dyck lived in Haarlem for most of his life, but he was born in Delft. He was a cousin of Pieter Cornelisz van Rijck, whose father Cornelis first had a brewery in Delft before moving to the brewery "De Olyphant" in Haarlem. In 1600 he was documented as being in Rome, where he was a good friend of Joseph van Arpino and witnessed him being cured of an ailment with Olio del gran Duco, an oil given to him by the Pope's personal physician, with which he smeared himself all over his body. Thanks to this miracle cure, Arpino could finish an altarpiece in the Archbasilica of St. John Lateran.
In 1606 he returned to the Netherlands, where he settled in Haarlem and became one of Karel van Mander's sources on modern Italian painters for his Schilder-boeck. He probably lived with or near his uncle, the brewer Cornelis van Rijck. Like the young Frans Hals and other assistants to Karel van Mander, Floris is not listed with his own entry in that book, though he was already an established painter on his return from Italy. After Karel van Mander's death, Floris joined the Haarlem Guild of St. Luke in 1610 and became dean in 1637. On 11 September 1625 he married for the second time to Cornelia Jansdr. Vlasman and the wealthy Gijsbert Claesz van Campen was his only witness.
He was influenced by Osias Beert and Clara Peeters and is considered the inventor of the banketje (banquet still life genre similar to breakfasts, or ontbijtjes), together with Nicolaes Gillis. Besides Nicolaes Gilles, he influenced the painters Floris van Schooten, Pieter Claesz, and Roelof Koets. He died in Haarlem.