Siletz can refer to:
- Confederated Tribes of Siletz, a federally recognized tribal entity from the U.S. state of Oregon
- Siletz (tribe), a nearly extinct tribe of Native Americans from Oregon, now absorbed into the multi-tribal Confederated Tribes of Siletz
- Siletz Reservation, an Indian reservation in Oregon, home to the Confederated Tribes of Siletz
- Siletz Bay, a body of water in Oregon
- Siletz, Oregon, a city in Oregon
- Siletz River, a river in Oregon
- Siletz River Volcanics, a voluminous province of volcanic deposits ranging from Northern California to Vancouver Island.