Eugene Jo became separated from a group of fellow hikers after having lunch and traversing a trail on June 22. A massive search was launched, comprised of about 75 people divided into 11 teams.
There was no sign of Jo until about 11 a.m. Saturday, when he was spotted by the Los Angeles County Sheriff's Department's Altadena Search and Rescue Team. He was several miles away from the trail of the original hike.
"Search team reports they have found 73 year old Mr Jo, after a week in the wilderness, he is alive!," the Montrose Search and Rescue Team said in a tweet.
Jo was airlifted to a hospital after being located in Devil's Canyon and hoisted into a helicopter by tactical medics with the sheriff's Special Enforcement Bureau, according to the agency.
He did not appear to have any traumatic injuries, authorities said.