Brad Gobright, 31, fell around 300 meters (1,000 ft) to his death in El Portero Chico in northern Mexico.
His companion, fellow climber Aidan Jacobson, 26, fell a shorter distance and survived with injuries.
Gobright was best known for free soloing, or climbing without any safety gear, but at the time the two were rappelling, a technique using ropes.
Climbers descend a rock face by using a doubled rope coiled around the body but the method is described by experts as one of the most common causes of deaths in the sport.
"We started rapping," Mr Jacobson told the Outside website. "I was a bit above him. I was on the left. He was on the right. Then all of a sudden, I felt a pop, and we started dropping."
While Mr Jacobson crashed through a bush, which cushioned his fall, before striking a ledge, Gobright fell to his death.
"It was basically a blur," Mr Jacobson added. "He screamed. I screamed. I went through some vegetation, and then all I remember is seeing his blue Gramicci shirt bounce over the edge."
Tributes to Gobright, who once held the coveted speed record on the Nose of El Capitan in Yosemite, have come in from across the climbing world.
"The climbing world lost a true light. Rest in peace," wrote Alex Honnold, focus of the Academy Award-winning documentary Free Solo.
"He had a magic about him on the rock, unlike anyone I've ever met," wrote Alice Hafer, one of Gobright's climbing partners.
"He was so supportive and encouraging, always pushing me harder and believing in me."