Thessalus is a name that may refer to:
Thessalus, the name of several figures in Greek mythology Thessalus (physician), Greek physician (5th - 4th centuries BCE) Thessalus of Tralles, Roman physician (1st century CE) Thessalus (actor), a tragic actor in the times of Alexander the Great This Thessalus appears as a character in Steven Pressfield's The Virtues of War