During hospitalization, the car was parked in the parking space downstairs in the hospital ward, and the upstairs building collapsed, knocking the car over. Who is responsible for this?

Throwers and hospitals. People who throw things should bear corresponding responsibilities. Because it was his behavior that caused the damage to the vehicle, he should be responsible for his own behavior. And hospitals should also be responsible, because hospitals have the responsibility to ensure the safety of their buildings and facilities and prevent patients' property from being damaged. If the hospital fails to take necessary safety measures, or the safety measures are insufficient, resulting in vehicle damage, then the hospital should bear corresponding responsibilities.