Mount Veniaminof () is an active stratovolcano on the Alaska Peninsula. The mountain was named after Ioann (Ivan Popov) Veniaminov (1797–1879), a Russian Orthodox missionary priest (and later a prominent bishop in Russia) whose writings on the Aleut language and ethnology are still standard references. He is a saint of the Orthodox Church, known as Saint Innocent for the monastic name he used in later life.
The volcano was the site of a colossal (VEI 6) eruption around 1750 BCE. This eruption left a large caldera. In modern times the volcano has had numerous small eruptions (over ten of them since 1930), all at a cinder cone in the middle of the caldera.
Veniaminof is one of the highest of Alaskan volcanoes. Partly for this reason, it is covered by a glacier that fills most of the caldera. Because of the glacier and the caldera walls, there is the possibility of a major flood from a future glacier run.
The volcano recently began erupting on September 3, 2018 as magma broke through the summit and flowed down its slopes as a lava flow. Despite starting off as an effusive eruption, by November 20, the eruption became more intense and ash was reaching 20,000 feet, prompting the AVO to give a warning for aviation because of the ash posing a threat to aviation. Even an ashfall warning was issued for the nearby town of Perryville.
In 1967, Mount Veniaminof was designated as a National Natural Landmark by the National Park Service.