| Kozbükü Tunnel Kozbükü Tüneli | |
| Location: | Fatsa, Ordu Province |
| Coordinates: | 40.9944°N 37.6439°W |
| Status: | Operational |
| Startwork: | 1997 |
| Operator: | General Directorate of Highways |
| Traffic: | automotive |
| Construction: | Nurol-Tekfen-Yüksel joint venture |
| Length: | 261and |
| Lanes: | 2 x 2 |
| Speed: | 80km/h |
Kozbükü Tunnel (Turkish: Kozbükü Tüneli), is a highway tunnel constructed in Ordu Province, northern Turkey.
Kozbükü Tunnel is part of the Samsun-Ordu Highway within the Black Sea Coastal Highway, of which construction was carried out by the Turkish Nurol-Tekfen-Yüksel joint venture. The 261and-long twin-tube tunnel carrying two lanes of traffic in each direction is flanked by 116--long Kadıoğlu Tunnel in the west and 170--long Tekkebak Tunnel in the east on the same highway.
The tunnel was opened to traffic on April 7, 2007 by Turkish Prime Minister Recep Tayyip Erdoğan. Dangerous goods carriers are not permitted to use the tunnel.
