Jacob Huysmans (c.1633–1696), was a Flemish portrait painter. He moved to England during the reign of Charles II where he became one of the fashionable painters of the court. His chief portraits are those of Izaak Walton and Catherine of Braganza, Charles II's wife (both displayed on the National Gallery, London).
He was a pupil of Gilles Backereel and Frans Wouters and came over to England from - presumably - Antwerp. His first works were pastiches of work from Anthony van Dyck. As a Roman Catholic he was favoured by Catharine of Braganza. When Samuel Pepys visited his workshop in Westminster on 26 August 1664, he described him as a 'picture-drawer ... which is said to exceed Lilly (Lely). Huysmans's most important portrait of Catharine of Braganza, Queen Catharine as a Shepherdess (c. 1664; Brit. Royal Col.), was one of the pictures Pepys saw on that occasion. Painting his subjects as sheperdesses with clothing embellished with embroidery and jewellery were typical of his style.