Josiah or Yoshiyahu or Joshua (literally meaning "healed by Yahweh" or "supported of Yahweh"; c. 649–609 BCE) is a king of Judah (641–609 BC) who institutes major reforms.

Josiah is credited by most historians with having established or compiled important Jewish scriptures during the Deuteronomic reform that occurred during his rule.

Josiah becomes king of Judah at the age of eight, after the assassination of his father, King Amon, and reigns for thirty-one years, from 641/640 to 610/609 BCE.

He is also one of the kings mentioned in the genealogy of Jesus in the Gospel of Matthew.