The pop star's comments are published just days after she was voted the “worst celebrity influence for teens” for the second year in a row in a survey conducted by AOL website Just So You Know.
A video of the 18-year-old singer smoking a bong allegedly filled with the herb salvia was posted on the internet in December.
Speaking about the incident, Cyrus tells US Marie Claire: 'I'm not perfect… I made a mistake… I'm disappointed in myself for disappointing my fans.'
When it is suggested that her bong-smoking antics were no different to thousands of American teenagers, the Disney star says: 'But they're not Miley Cyrus. They're not role models.
'So for me it was a bad decision, because of my fans and because of what I stand for.'
The former Hannah Montana star – who has been heavily criticised for filming raunchy pop videos for her last album, Can't Be Tamed – admits she is concerned about what her fans think of her, especially when it comes to her music.
But she says: 'What I never wanted was for my fans to ever feel like I betrayed them… to feel like I said I was something then turned around and was something that I'm not. But I've never, ever claimed to be perfect.
'I mean, since I've started the show, I've always said,: 'I'm gonna make mistakes'. I know this. And I think that that is one of the reasons why people related to me. Why kids related to me.'