The 'Wrecking Ball' singer was speaking in her new interview with Paper magazine, for which she appears on the cover naked and covered in mud, holding her own pet pig Bubba Sue.
"I am literally open to every single thing that is consenting and doesn't involve an animal and everyone is of age," Cyrus said. "Everything that's legal, I'm down with. Yo, I'm down with any adult - anyone over the age of 18 who is down to love me.
"I don't relate to being boy or girl, and I don't have to have my partner relate to boy or girl."
She went on to recall how she had first discussed her feelings towards women with her mother Tish Cyrus eight years ago.
"I remember telling her I admire women in a different way. And she asked me what that meant. And I said, I love them. I love them like I love boys," she said.
"And it was so hard for her to understand. She didn't want me to be judged and she didn't want me to go to hell. But she believes in me more than she believes in any god. I just asked for her to accept me. And she has."
The summer 2015 issue is released on June 22, with the cover feature focusing on Cyrus's non-profit Happy Huppy Foundation, which she has set up to help homeless and LGBT children.
