The name Clearchus or Clearch may refer to:

• Clearchus of Athens, Greek comic poet of unknown date
• Clearchus of Heraclea (c. 401 BCE – 353 BCE), Greek tyrant of Heraclea Pontica
• Clearchus of Rhegium (fl. 5th century BCE), Greek sculptor, pupil of Eucheirus, teacher of Pythagoras the sculptor
• Clearchus of Soli (4th–3rd century BCE), Greek author and philosopher, pupil of Aristotle
• Clearchus of Sparta (c. 450 BCE – 401 BCE), Greek general, son of Rhampias
• Clearchus (consul 384), Roman consul in 384 CE