The Bridesmaids star told GQ magazine that he blames his choice of roles for the fact that he is not viewed as "sexual".
"They see me more like a guy they would like to set their sister up with," said the actor, who married journalist and presenter Dawn Porter in August.
"I play very sweet characters, so people look at me like I'm the kid from The Wonder Years, rather than Brad Pitt."
Last year, O'Dowd tried to break away from 'nice-guy' roles and filmed sex scenes in the TV adaptation of The Crimson Petal And The White for the BBC.
The 32-year-old said that he wants a second chance to portray such scenes after experiencing unfavourable filming conditions the first time around.
"It was weird because the first time I was naked, I had to get out of a coldish bath, and I was like, 'Oh, great'," he explained.
"I'd do it again. Please give me the opportunity!"
O'Dowd also joked that a sex tape featuring him and his new wife won't be making its way online anytime soon.
"Well, so many of my sex tapes are already online that I feel I don't want to saturate it," he quipped. "Though you're only as good as your last job - if I put in a great performance sexually, it would do nothing but advance my career."
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