The international superstar flew to Cabo San Lucas in Mexico for the wedding of her high school bestie Bo O'Connor.
Gaga took her bridesmaid duties seriously for her friend's big day, holding the bride's bouquet during the ceremony and helping her with her veil.
The singer and other bridesmaids all wore dresses by versatile bridesmaid company Two Birds – whose classic ballgown style dresses can be worn over 15 ways to flatter all figures.
Gaga opted to style hers as a halter neck with a plunging neckline and wore what we're presuming is a long blonde wig, in a side swept style. All the bridesmaids accessorised their hair with a big pink flower.
Gaga, real name Stefani Germanotta, attended without her actor boyfriend Taylor Kinney as he is busy filming The Other Woman with Cameron Diaz in New York.
However she did bring her make-up artist Tara Savelo along to work her magic on the bridal party.
Doesn't Gaga look stunning?
Gaga's bridesmaid dress is available now, £250, twobirdsbridesmaid.co.uk
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