Johann Wilhelm Baur, Joan Guiliam Bouwer, or Bauer (Strasbourg, 31 May 1607 - Vienna, 1 January 1640) was a German engraver, etcher and miniature painter.

He specialized in watercolors of architectural follies in perspective, and for this reason was often employed to make pictures of gardens.

[3] According to Cornelis de Bie, Baur lived with Karel Škréta (Carolus Creten) while he was in Rome.

Many of his drawings of Ovid's stories, the passion of Christ in 24 plates, and scenes of daily life in Rome (with costumes of various nationalities) were engraved by Melchior Küsel of Augsburg.

[3] He died in Vienna of a sudden illness while on a commission by Ferdinand III, Holy Roman Emperor.