Juliaen Teniers or Juliaan Teniers (Antwerp 1572–1615) was a Flemish painter and one of the members of the extended Teniers family of painters.
Juliaan Teniers was born in Antwerp. He was the half-brother of David Teniers the Elder and the uncle of David Teniers the Younger. He married Suzanna Coignet, the sister of the painter Gillis II Coignet on 23 April 1595. He had at least three children: Jan Baptist, Melchior en Joanna.
Juliaan Teniers became a master of the Guild of St. Luke in 1595 and he joined the Armenbus. He and his wife lived in the Koningstraat until 1597, when they bought the house De Roos in the Vaartstraat. Between 1595 and 1608 he had at least eleven pupils, of whom only Gaspar van den Hoecke and his half brother David the Elder still have any claim to fame.
Juliaan Teniers died shortly before 11 March 1615.
Together with David Juliaan painted scenes for plays performed during the Joyous Entry of the Archdukes in Antwerp. His paintings are only known through inventories, which make clear that he sometimes cooperated with Joos de Momper and Claes van Cleve.