The pop songstress has been increasingly pictured with her tongue hanging out of her mouth over the last year - even while she is performing and shooting her music videos.
But apparently, this is all down to a case of self consciousness.
Speaking in a candid interview with journalist Barbara Walters, Miley revealed the real reason behind her pulling bizarre faces.
She said: "I get embarrassed to take pictures. That's actually the truth. I'm so embarrassed because people are taking pictures of me and I don't know how to smile, and just be awkward, so I stick my tongue out, because I don't know what else to do."
The 21-year-old spoke to Barbara as part of her ABC News special about the 10 Most Fascinating People Of 2013.
And of course, Miley made the cut!
During her chat she also touched on her split from fiancé Liam Hemsworth, telling Barbara that she clung onto their relationship for so long because she was afraid of being alone.
Despite her sensitive and almost timid interior, on the surface Miley oozes confidence and self assurance.
From her provocative outfits, to flashing her nipples in a bid to challenge censorship laws in America, we would never have guessed that the chart-topping singer was the embarrassed type!
Barbara Walters' full interview with Miley Cyrus airs during Barbara Walters Presents: The 10 Most Fascinating People of 2013 in the US on Wednesday night.
What do you think of Miley's reason for not smiling? Let us know below, as the best comment from across the website each week wins £50!
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