Lisa Marie Presley -- Files For Divorce

Lisa Marie Presley has filed for divorce ... TMZ has learned.

Elvis' 48-year-old daughter wants full custody of the couple's twin 7-year-old daughters. She wants to give her musician hubby, Michael Lockwood, visitation, but only monitored.

Sources connected with the couple tell TMZ they had a postnup ... the divorce docs say nothing about any division of property.

Lisa Marie cites irreconcilable differences for the divorce and she lists the date of separation as June 13th. One source made it clear, "She doesn't want any of his money."

She is not asking for any spousal support or child support.

The couple married in 2006.