Chris Seelye, of Darby Montana, died Monday night after becoming ill on the fire line near Entiat.
Seelye was working as a timber faller on the Klone Fire and was treated by incident medical personnel and transported to a nearby hospital, where he died.
The Klone Fire is estimated to be about 656 acres and primarily burning timber that was severely impacted by disease and insects.
About a dozen tree fallers were called in to assist in efforts with the Wenatchee Complex Fire.
Tree fallers are called in to wildfire situations to professionally remove hazardous trees to allow firefighters to construct a fire line- or to eliminate a safety threat.