Heidi Klum -- Gets Topless Protesters in Her Face On 'Top Model' Stage

Heidi Klum just got an eyeful of boobies -- and some anti-Heidi messages -- when two topless women ran onstage during the finale of "Germany's Next Top Model."

It was quite a scene ... the bare-breasted women got right in Heidi's face ... exposing messages written on their chests, like "HEIDI HORROR PICTURE SHOW."

At least one security guard got a handful of underboob while dragging away one of the women ... perks of the job.

Heidi seemed unfazed by the interruption -- and it's unclear what the protesters' beef was with her ... or shirts.

But who cares? BOOBIES!