Cephissus (ancient Greek: Κήφισσος; ), Cephisus, Kephisos, or Kifisos may refer to:
Waterways in Greece
Cephissus (Argolis), a river in Argolis, a tributary of the Inachus River
Cephissus (Boeotia), a river in northern Boeotia
Cephissus (Athenian plain), a river in Attica flowing through the Athenian plain
Cephissus (Eleusis), a tributary of the Saronic Gulf from the Eleusinian plain
Cephissus (Salamis), a river on Salamis Island
Other
Cephissus (mythology), a man changed into a sea monster by Apollo
Cephissus, a Martian canal, per List of Martian canals
Battle of the Cephissus, 15 March 1311 conflict between the Frankish Greek forces of Walter V of Brienne and the mercenaries of the Catalan Company Cephisus (spittlebug), a genus of insects in the family Aphrophoridae