The Young Adult star said that his first foray into entertainment came not as an actor or a comedian, but as a small-time wedding entertainer.
"I answered an ad and that was how I spent my weekends, presiding over weddings in northern Virginia," he recalled to Parade.
Oswalt further explained that his disc jockeying days were short-lived because of his 'snobbish' music taste.
"I was a budding music snob and impatient with people, but in my defence, I never lost it," he quipped.
Oswalt previously claimed that it was a "nightmare" to film a love scene with his Young Adult co-star Charlize Theron.
Young Adult is now playing in US cinemas and is released in the UK on February 3.
> Young Adult star Patton Oswalt: 'High school is not reality'
> Charlize Theron is the female Jon Hamm, says Patton Oswalt
Watch a trailer for Young Adult below: