The Script frontman claimed that he snubbed the Bad Teacher actress as he is in a "very happy" relationship, but said that he might take her out if he becomes single.
"Cameron Diaz once asked me out," The Sun quotes him as saying. "It was when we were both in New York on the Today show. She gave her number to my management.
"I didn't call her, though. I'm very happy with my girlfriend. To be honest, I wasn't even tempted. If me and my girlfriend broke up I'm sure I'd track her down."
However, the 'Breakeven' singer accepted that he wouldn't be as lucky with the ladies if he wasn't famous.
"I get to say 'no' to some of the most beautiful girls in the world who would not have come anywhere near me if I was not in the band," he said.
"They would not have looked twice at me in the past - maybe even slapped me across the face if I'd approached them in a club."
Diaz split from long-term boyfriend Alex Rodriguez last summer and was subsequently linked to P Diddy.
Watch the video for The Script's 'Breakeven' below: