Attu may refer to:

• Attu Island in Alaska, the westernmost island of the Aleutian Islands chain
• The Battle of Attu, the primary land battle in the Aleutian Islands campaign of World War II, which took place on Attu Island in May 1943.
• Attu Station, Alaska, a LORAN station on Attu Island
• Attu (Greenland), a settlement in western Greenland
• Attu (film), a 2017 Indian gangster film
• An extinct dialect of the Aleut language
• An island in Pargas, Väståboland, Finland
• A breakfast dish in Andhra Pradesh, India; see List of Indian dishes