The actress - who has worked with MacFarlane on Family Guy for over a decade - explained that she was attracted to the script in part because of the talking bear element, rather than in spite of it.
"Listen, I knew what I was getting myself into," Kunis told The Hitlist. "It's not like I thought, 'I didn't know there's a talking teddy bear in this movie'. I knew what it was doing. I thought that was great."
Kunis went on to discuss her co-star Mark Wahlberg, saying: "He's really funny and warm in real life. He's very shy. He's a family guy.
"Mark is like a guy's guy, but he's very sweet. He's got a solid sense of humour, and he's willing to do anything for a joke. You have to respect a guy for that."
Wahlberg has described his role in Ted as very different from parts he has played previously, and has also suggested that he found working with a teddy bear easier than with another actor.
Ted is released today (June 29) in the US, and on August 1 in the UK. Watch the red band trailer below: