The Wiyot massacre refers to the incidents on February 26, 1860, at Tuluwat, near Eureka in Humboldt County, California. In coordinated attacks beginning at about 6 am, White settlers murdered 80 to 250 Wiyot people with axes, knives, and guns. The February 26 attacks were followed by similar bloody attacks on other Wiyot villages later that week in what were part of the broader California Genocide.

Tuluwat Island is located on Humboldt Bay within the city of Eureka, California. The 1860 Wiyot Massacre was perpetrated in the village of Tolowot or Tuluwat on this island. A National Historic Landmark encompasses the midden at Gunther Island Site 67. Since October 21, 2019, the Wiyot people have had the land deed to most of the Island.