Cardi B Sings Whitney Houston While Leaving Thom Browne Fashion Show

Cardi B couldn't pass up the opportunity to hop on the mic in the streets of France ... singin' a few bars of a Whitney Houston classic while leaving the Thom Browne Fashion Show.

Cardi was on her way out of the designer's show Monday in Paris, telling the photog the event was great ... but as she approached her ride, she got offered the impromptu performance from a nearby busker.

Cardi initially shot it down, using nerves as an excuse -- but if ya know Cardi, it shouldn't come as a shock she ended up making her way to the artist, singing the beginning of "I Will Always Love You."

Folks gettin' to hear Cardi sing the hit only got a taste, though ... because she laughed her performance off before finally jumping in the car.

Safe to say, Cardi's in a better place compared to last week -- as we reported, she dragged her husband Offset online after he publicly accused her of cheating on him in the past.

She clearly wasn't having any of it ... cursing him out and claiming she'd hit him with a bottle if he ever made those claims face-to-face.