A guy was shot twice in a Bronx drug deal gone wrong — despite rolling up with a bulletproof vest, police said.

The shooting unfolded just before 6 p.m. on Wednesday when the 35-year-old man went to buy some marijuana near 2077 Southern Blvd., cops said.

But before he could make the deal, someone came up behind him and shot him twice in the back, according to police.

The victim was then captured on video running into a grocery store on E. 180 Street and hiding behind the counter, where he pulled off the bulletproof vest, cops said.

The man was taken to Jacobi Hospital where he is expected to survive. It was unclear whether the bullets struck the vest or the man.

No arrests have been made.