Lisa Marie Presley: My Ex took a Hunka-Hunk of My Money

Lisa Marie Presley filed for divorce in part because she believes her husband has played fast and loose with her money.

TMZ broke the story, Lisa Marie filed divorce docs Friday to end her 12 year marriage to Michael Lockwood. Her lawyer, Ron Litz, says Michael ran the finances during their marriage and she didn't monitor any of it, including the Elvis money that came in.

We're told when the relationship started getting rocky, she noticed things ... in particular an enormous American Express bill ... more than $109,000. Shortly after she spotted the charge, AmEx sued her.

We're told Lisa Marie's legal team has now opened a forensic audit to determine where all the money went during their marriage.

As we reported, the couple had a postnup. We're told that document makes it clear ... all the Elvis money is hers.

We made several attempts to reach Michael, with no luck.