Lady Gaga reportedly paid the highest ever price for an Alexander McQueen design.
Fashion icon Daphne Guinness put a huge collection of her haute couture wardrobe up for bidding at Christie's in London, including several items by the late designer.
The Born This Way singer, who was a big fan of the couturier's work, gave the charity auction a boost by outbidding rivals to buy a dress.
She allegedly spent a record-breaking $136,400 via her telephone bids.
The star is now the proud owner of a 2008 ivory silk gown, called The Girl Who Lived In The Tree.
Socialite Daphne sent out a special thank you message to Lady Gaga for her huge purchase.
Daphne said: ''I'm overwhelmed by how many bidders took part ... and I'm particularly moved by Lady Gaga's support for the foundation. I like her very much, and it's lovely to see the nascent beginnings of something that may help other people.''
The auction raised $747,200 for the Isabella Blow Foundation, set up in memory of the late fashion guru.