Isaeus (Greek: Ἰσαῖος Isaios; fl. early 4th century BC) was one of the ten Attic orators according to the Alexandrian canon. He was a student of Isocrates in Athens, and later taught Demosthenes while working as a metic logographer (speechwriter) for others. Only eleven of his speeches survive, with fragments of a twelfth. They are mostly concerned with inheritance, with one on civil rights. Dionysius of Halicarnassus compared his style to Lysias, although Isaeus was more given to employing sophistry.