Norway's Lasse Kjus took silver while another Austrian Stephan Eberharter finished in bronze position.
The Grizzly course proved to be little problem for Strobl, who produced a near faultless display to win in a time of one minute 39.13 seconds.
"I don't think this will change my life - I was happy
before"
Gold medallist Fritz Strobl
"It's just a great, great feeling. It's overwhelming," said Strobl.
Kjus, who won silver in Nagano four years ago, had to settle for the same result again finishing in 1:39.35.
Eberharter, the pre-race favourite and this season's World Cup downhill champion managed a time of 1:39.41.
The 29-year-old Strobl becomes the sixth Austrian to have won an Olympic downhill title.
Strobl facts
Age: 29
Country: Austria
Profession: Policeman
Past Olympics: 1998 Nagano - 11th
Other successes:
Fourth in downhill at 1997 World Champs
sixth in downhill at 2001 World Champs
Nickname: Fritz the Cat
"It was just the perfect day," added Strobl.
"The weather was beautiful, the course was fine and I was able to run my race the way I had planned.
"I don't think this will change my life. I was happy before."
Eberharter, who is favourite for the super-G remained upbeat despite the uncharacteristic performance.
"It was not really my race. I made two or three small mistakes, in particular coming into the final wall," said Eberharter.
"I won the bronze, I didn't lose gold."