Seattle physician Jonathan Sugarman was on an expedition by Washington state's International Mountain Guides.
The company said his death was "not the result of a climbing accident".
It confirmed on its website that a team member died on the mountain at Camp 2, two levels higher than base camp.
“It is with deep sorrow that IMG reports the death of one of our Everest 2023 team members at Camp 2," said Eric Simonson, chief executive of International Mountain Guides.
“We can confirm that this event was not the result of a climbing accident or route condition that would be of potential impact or safety concern to any other teams on the mountain.”
Sugarman and the other IMG expedition climbers began moving up the mountain on April 29, expedition posts on the website said.
The doctor was a clinical faculty member known for his work in Native American health care and international health, the University of Washington said on Twitter.
Three Sherpa climbers died after falling into a crevasse on a treacherous section of Mount Everest just above base camp in April.
Hundreds of foreign climbers and a similar number of Nepalese guides and helpers were expected to try to scale the 8,849m mountain during the main climbing season that began in March and ends in late May.