Both musicians attended a show by Iris Van Herpen, who styled their ethereal looks.
The Grammy-winning rapper turned heads in a look designed by Daniel Roseberry.
Beyoncé, Jay-Z, Rihanna, A$AP Rocky, Kim Kardashian and Jared Leto were among the stars seated in the front row.
The post comes just hours after Lavigne's ex-fiancé Mod Sun addressed their breakup on Instagram.
The pop singer strutted the runway for Parisian designer Pressiat.
From Doja Cat to members of BTS, see the artists who showed up in the City of Lights.
