Officials say the two were hiking on top of the Baldy bowl when the avalanche occurred. They slid down about 200 to 300 feet into the bowl. Both were injured, one seriously.
The seriously injured hiker was hoisted into a helicopter and transported for medical attention. The copter then returned for the second hiker.
Firefighters said given the distance they fell, the incident could have been much worse.
"It could have been a body recovery," said Battalion Chief Doug Nelson with the San Bernardino County Fire Department.
Mount Baldy is in the San Gabriel Mountains, north of Upland.