Peter Gschnitzer made his World Cup début in 1977 at Königssee, immediately achieving a win in doubles with his long-term partner Karl Brunner. They twice won the overall World Cup, in 1978 and 1979. Gschnitzer participated in two Olympic Winter Olympics, winning a silver in doubles at Lake Placid in 1980. He also won a silver medal at the World Championships in 1977 and one bronze in the European Championship in 1979, both in doubles. Gschnitzer won two World Cups in doubles. In the World Cup overall standings he was twice ranked first in doubles, in 1978 and 1979, always teaming up with Brunner.