Schlierenzauer's opening jump of 105.5m had put him out in front, and he followed up with 97m for a winning total of 288.5 points.
Taku Takeuchi came in five points behind in second place with 99 m and 100.5m while Richard Freitag was third.
Schlierenzauer said: "I'm very happy and proud that I was able to win today. My first jump was very good and I also had some luck with the conditions. These two things combined brought me the lead after the first round. Taku was a dangerous opponent today, his technique is good and it's only a matter of time until he stands on top of the podium."