The woman, a guest at the show, ran down from her seat and joined the models as they did their last walk along a spectacular set recreating the roofs of Paris inside the Grand Palais.
With security guards left floundering, supermodel Gigi Hadid eventually confronted the gatecrasher as she tried to further upstage the models, and escorted her off the set.
The daring infiltrator was dressed from head to toe in a black and white Chanel-like tweed suit and hat, and slipped unnoticed onto the catwalk.
Guards only realised that she had joined the models when it was too late to intervene.
“I couldn’t stop laughing because the hapless security guards couldn’t spot her in the line-up,” said the New York Times’ Elizabeth Paton.
By then the woman — who has yet to be identified — was giving it her all, waddling down the catwalk with her hands on her hips like a supermodel.