The clip, filmed in 2005 as Trump chatted with Access Hollywood presenter Billy Bush, appears to have been captured as Bush accompanied the presidential candidate to a soap opera set.
He can be heard claimed he 'moved' on an unnamed woman, but she rejected him.
The video was taken just a few months after he married third wife Melania, according to the Washington Post.
It begins with just audio of the two chatting, with both men's microphones switched on.
And Mr Trump can be heard saying: “I did try and f*** her. She was married.
“And I moved on her very heavily. In fact, I took her out furniture shopping. She wanted to get some furniture.
"I said, ‘I’ll show you where they have some nice furniture.’ I moved on her like a bitch, but I couldn’t get there. And she was married.”
They can then be heard gasping over another woman, thought to be actress Arianne Zucker, who arrives to meet the pair.
And Trump then adds: “I’ve gotta use some tic tacs, just in case I start kissing her.
“You know I’m automatically attracted to beautiful -- I just start kissing them. It’s like a magnet. Just kiss. I don’t even wait.”
“And when you’re a star they let you do it. You can do anything.
“Grab them by the p****. You can do anything.”
A statement from Mr Trump said: “This was locker room banter, a private conversation that took place many years ago.
"Bill Clinton has said far worse to me on the golf course - not even close. I apologize if anyone was offended.”
Trump has been repeatedly criticised over his comments towards women throughout his presidential campaign.