Demonstrators say 500,000 people live within a few blocks of the hospital site and other medical centers are too far away.
Right now, there are plans to open an urgent care center and build condos in place of Saint Vincent's.
It's something area residents say they plan to fight.
"An important thing to note here is that it is not a done deal. They're not going to be able to do what they want without our community, our city and our state's approval and they're not going to get that approval without a hospital," said Paul Newell from the Coalition for New Village Hospital.
Saint Vincent's had financial issues for years first filing for bankruptcy back in 2005.