It was Korea Air's second such threat in two days, the Canadian Broadcasting Corp. reported.
Flight 72, a Boeing 777, had taken off from Vancouver International Airport about 2:30 p.m., bound for Seoul with 149 people on board, the CBC said.
A Korean Air spokesman told the network the aircraft was off the coast of British Columbia was diverted to the military base after a threat was called in to the airline's Los Angeles office.
Two U.S. Air Force F-15 fighter jets were scrambled from a base in Portland, Ore., to escort the jetliner, Victoria's Search and Rescue Co-ordination Center said. The plane landed without incident about 5:50 p.m.
It was not clear when the passengers would resume their travels.
On Monday Korean Air Flight 72 was the target of a phoned-in threat, forcing a 2-hour delay in take-off, James Koh of Korean Air's Vancouver office said. Koh said the caller spoke English and voice recordings were made of both calls.