Strobl finished 11th in the downhill four years ago at Nagano and had just one downhill victory this season on the World Cup circuit. But his time of 1 minute, 39.13 seconds made him the first Austrian to capture a gold medal in the marquee alpine event since Patrick Ortlieb in 1992 at Albertville.
"Yes, I thought I could do it," said Strobl, who was second in each of his two training runs. "I thought I had a chance. I had a great feeling this morning."
Kjus was just .22 seconds behind Strobl and settled for the silver, his fourth Olympic medal. He also finished second in the downhill at Nagano behind France's Jean-Luc Cretier.
"I had a good day today, everything went my way," the 31-year-old from Oslo said. "This is a hard course, but I have the confidence and managed to make something out of it."
Pre-race favorite Stephan Eberharter took the bronze with a time of 1:39.41 as three Austrians finished among the top six.
"The last turn up there, I entered a rough section and I braked so hard," Eberharter said. "It wasn't my run. But I am close to the winner."
Strobl is a 29-year-old police officer from Gerlamoos who missed the 1992 Games at Albertville due to a knee injury. However, he ranked third in the world in the downhill in 1996-97 and again in 2000-01.
Teammate Christian Greber, who finished sixth, said he was not surprised by Strobl's performance.
"I have known him for five or six years and I know what he can do. I think he is the best Olympic champion that we can wish for because he's a very good racer," Greber said.
Marco Sullivan was the top American in ninth place, 1.24 seconds behind Strobl. Countryman Daron Rahlves was a disappointing 16th.
"I didn't get on the podium, but for me, a top-10 finish was what I was shooting for," Sullivan said.
Not so for Rahlves, who was third in Thursday's practic run.
"I was trying to go back to the way I skied the first day -- smooth and relaxed," he said. "With super-G coming up next week, I've got another shot. And I'm looking forward to that race now."