Balthasar \b(a)-ltha-sar, bal-thasar\ as a boy's name is of Babylonian origin, and the meaning of Balthasar is "Baal protect the king". Along with Caspar and Melchior, one of the three wise men who brought gifts to the baby Jesus, though they are not named in the Bible. The name is a variant of the biblical king Belshazzar. Baldassare is the Italian form. Actor Balthazar Getty.

Balthasar has 8 variant forms: Baldassare, Baltasar, Baltazar, Balthasaar, Balthazaar, Balthazar, Balto and Belshazzar.

For more information, see also the related name Melchior.