He was the uncle of Isaac Mijtens (ca 1602-1666), a portrait painter in The Hague and Daniel Mijtens (ca 1590-ca 1647), a painter at the English court. He painted in the studio of another Flemish painter there called Anthoni Santvoort, who painted representations of Mary (Maria Magior) on copper. Mijtens was active in Brussels, Rome, Naples (where he was successful and worked for the court of the Viceroy), L"Aquila, and The Hague.
Van Someren married Mijtens" daughter and returned with her to Flanders.
Aert Mijtens painted altarpieces, historical and mythological paintings, and portraits. He died in Rome.
He was the first known member of a family of painters named Mijtens or Mytens.