Willem van Mieris (3 June 1662 – 26 January 1747) was an 18th-century painter from the Northern Netherlands.

He was born in Leiden as the son of Frans van Mieris sr. and brother of Jan van Mieris. He was a member of the Leiden Guild of St. Luke and a founding member of the Leidse Tekenacademie which opened in 1694. His pupils were Catharina Backer, Abraham Alensoon, and Hieronymous van de Mij. He retired in 1736 because he was partially blind. He died, aged 84, in Leiden. His works are extremely numerous and show the influence of Francis van Bossuit as well as his father. As an artist, he did not equal his father.

Van Mieris has works in the Victoria and Albert Museum as well as Cheltenham and Derby Museum and Art Gallery.