The 43-year-old actor says he rarely meets real fans, just people who want to make money from his autograph.
Asked how 'Star Wars' fans have responded to him, he told Details magazine: "I don't have any experience with them. I've never been to one of the conventions.
"The people I meet are the f***ers who want me to sign 'Star Wars' photos so they can sell them on the Internet or the people at premieres who are crushing children against barriers to get me to sign their f***ing picture of Obi-Wan Kenobi.
"They're not fans -- they're parasitical lowlifes and f***ing w****rs."
Ewan - who raises daughters Clara, 18, Jamyan, 13, Esther, 12, and Anouk, three, with wife Eve - was just 24 years old when he became a dad and reveals he thought he "knew it all" and can see his "idealistic" nature now reflected in his eldest child.
Ewan - who is currently starring in 'The Real Thing' on New York's Broadway - said: "You're very idealistic at that age. You think you know it all, and in a way, you do.
"I see it in my daughter Clara, who's just starting college in New York City.
"I remind her that I'll be giving her a call every night after the play is over, 'Where are we going?' She'd be like, 'F**k you, Dad. Get out of my life.' You're starting college, Clara...but I'm coming with you."
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