Pileus may refer to:
- Pileus (hat), a brimless cap
- Pileus (mycology), the "cap" of a mushroom
- Pileus (meteorology), a cloud formation
- the crown of a bird's head
- the scales on the top of lizard and snake heads
See also
- Jewish hat, pileus cornutus
- Plis (hat)
- Battle of Pileu (1819)