Dynjandi is a waterfall located in Arnarfjörður in the Westfjords region of Iceland. It is the largest waterfall in the Westfjords and has a total height of 100 meters Below it are five other waterfalls: Háifoss, Úðafoss, Göngufoss, Hundafoss and Bæjarfoss.

Dynjandi and other waterfalls in Dynjandisá and their surroundings were protected as natural monuments in 1981.