A Los Angeles Superior Court commissioner granted control over 17-year-old Frances Bean Cobain to Kurt Cobain's mother Wendy O'Connor and his sister Kimberly Dawn Cobain.
The court filing does not mention Love or give a reason for the guardianship.
In recent months, Love, former frontwoman of the band Hole, has been criticized for rambling online postings that have attacked a former bandmate and others. A fashion designer sued Love in Los Angeles earlier this year over some of the posts, claiming they were libelous.
A three-page order issued Friday was all that is publicly available on the guardianship.
Attorney Geraldine Wyle, who is handling the case for the mother and sister, calls it a private family matter and said no other comment would be issued.
Love's publicist Alan Nierob said in an e-mail he didn't have any details about the guardianship.
The court order, which is valid until February, grants Cobain's mother and sister no control over a trust established by the Nirvana frontman for his daughter. Kurt Cobain killed himself in 1994.
The guardianship was first reported by TMZ.com.
In September 2005, Love was sentenced to 180 days at a drug treatment facility for violating probation in three misdemeanor cases - one for illegal possession of painkillers, one for being under the influence of a controlled substance in public, and another for assault and battery.