The additions to Daniel comprise three chapters not found in the Hebrew/Aramaic text of Daniel. The text of these chapters is found in the Koine Greek Septuagint, the earliest Old Greek translation.

The three additions are as follows.

• The Prayer of Azariah and Song of the Three Holy Children: Daniel 3:24–90 inserted between verses 23 and 24 in the Protestant canon (v. 24 becomes v. 91), incorporated within the Fiery Furnace episode. When Shadrach, Meshach, and Abednego are thrown into a furnace for declining to worship an idol, they are rescued by an angel and sing a song of worship. In some Greek Bibles, the Prayer and the Song appear in an appendix to the book of Psalms.
• Susanna and the Elders: before Daniel 1:1, a prologue in early Greek manuscripts; chapter 13 in the Vulgate. This episode, along with Bel and the Dragon, is one of "the two earliest examples" of a detective story, according to Christopher Booker. In it, two men attempt to coerce a young woman into having sexual relations with them through blackmail, but are foiled under close questioning by Daniel.
• Bel and the Dragon: after Daniel 12:13 in Greek, an epilogue; chapter 14 in the Vulgate. In this tale, Daniel's detective work reveals that a brass idol believed to miraculously consume sacrifices is in fact a front for a corrupt priesthood which is stealing the offerings.