VEHICLE SIDE DOOR STRUCTURE AND VEHICLE OCCUPANT PROTECTION SYSTEM

To provide a vehicle side door structure and a passenger protecting system that, at a time of a side collision, can push a waist region of a passenger at an early stage over a wide surface area. A vehicle side door structure has: a door outer panel (40); a door inner panel (42) in which a service hole (44) is formed; a door trim (46) mounted to a vehicle transverse direction inner side of the door inner panel; an inner pad (56) provided, between the door inner panel and the door trim, so as to span, in a vehicle longitudinal direction, over an outer peripheral edge of the service hole as seen in a vehicle side view; and an outer pad (52) that is provided between the door outer panel and the door inner panel so as to overlap a vehicle transverse direction outer side of the inner pad as seen in a vehicle side view, and that has a first region that, at a time of a side collision, is pushed by the door outer panel and passes-through the service hole and pushes the inner pad toward the door trim side, and a second region that, at a time of a side collision, separates from the first region and pushes the inner pad toward the door trim side via the door inner panel.