Youmin Kim was visiting relatives in British Columbia before the nine-day tour of the western United States, Oregon State Police officials said.
Police also released the names of three other victims of the Sunday crash, including a woman from Washington state and a Korean couple who had been staying with relatives in Washington.
The bus plunged through a guardrail and 200 feet down an embankment Sunday while returning to Vancouver, British Columbia, on the final leg of the vacation tour. The trip was organized by a British Columbia travel agency that has yet to comment. Oregon's deadliest roadway crash since 1971.
Police have not publicly named four of the passengers who were killed. Lt. Gregg Hastings said the identification process has been slowed by factors such as the availability of legal identification, fingerprint and medical records.
In addition to Kim, the victims identified Wednesday are: Yongho Lee, 75, of Lynnwood Wash., Oun Hong Jung, 67, of South Korea and his Wife, Joong Wha Kim, 63. The couple had been staying with relatives in Bothell, Wash., before boarding the bus, police said.
Authorities earlier said 57-year-old Dale Osborn of Spanaway, Wash., died in the crash.
Vice Consul Chul Ho Choi, who went to Pendleton, Ore., from Seattle to help authorities with translations and to notify relatives, said five of the victims were South Korean citizens.
Another 38 people were injured, including driver Haeng Kyu Hwang, 54, of Vancouver, B.C. At least 10 remained hospitalized Wednesday afternoon at facilities stretching from Boise, Idaho, to Portland. State troopers have been going to hospitals with photographs of unclaimed property, including purses and luggage, in an effort to return items found at the scene.
The cause of the crash has yet to be released, and police have said it could take a month or more to determine whether the driver was at fault. The investigative team includes police and three National Transportation Safety Board inspectors.
The crash occurred near a spot on the interstate called Deadman Pass, at the top of a steep, 7-mile descent from the Blue Mountains. There were icy spots, but nothing unusual for this time of year.
"The crash happened on a pretty straight stretch before they head down the hill," said Tom Strandberg, a spokesman for the Oregon Department of Transportation.
The posted speed limit is 55 miles per hour for trucks and buses and 65 miles per hour for cars. Drivers, however, are required to go slower in treacherous conditions.
Despite its foreboding name - coined in pioneer times long before the automobile - the pass had not been deadly in the 21st century. In the past 10 years, there had been 59 accidents, but no deaths, on that stretch of highway, Strandberg said.
Transportation Department records show Sunday's crash to be the state's deadliest since a two-car collision in Portland killed nine in October 1971.
Six years before that, a Greyhound bus lost control on an icy section of Interstate 5 in southwest Oregon. The Christmas Eve crash killed 14 people