Festus Hommius (10 February 1576 – 5 July 1642) was a Dutch Calvinist theologian.
From 1602 preacher at Leiden, he rapidly became drawn into the conflict around Jacobus Arminius.
Hommius became a partisan of Franciscus Gomarus, the opponent of Arminius on the Leiden faculty.
He published polemical books and attended conferences with Remonstrant leaders such as Johannes Wtenbogaert.
He was a leading publicist of the Contra-Remonstrants, attacking the Five Articles of Remonstrance.