Koss can refer to:
- Koss Corporation, United States-based company that designs and manufactures headphones.
- Johann Olav Koss, a Norwegian Olympic speed-skater and official.
- Koss, an album by Paul Kossoff.
- Koss (musician), an alias for Japanese music producer and DJ Kuniyuki Takahashi.
- Koss River in South Sudan
- Koss (Star Trek), character in Star Trek: Enterprise who married T'Pol.