SIDE DOOR STRUCTURE OF VEHICLE, SIDE DOOR, VEHICLE, AND METHOD OF FORMING SIDE DOOR

There are provided an outer member (10), an inner member (30, 31, 32) including a front-side vertical wall portion (41) and a rear-side vertical wall portion (42), an impact bar (46) extending from the front-side vertical wall portion (41) to the rear-side vertical wall portion (42), a hinge-reinforcement member (54) where a hinge (51) is attached to the front-side vertical wall portion (41), and a latch-reinforcement member (55) where a latch device (52) is attached to the rear-side vertical wall portion (42). The front-side vertical wall portion (41) and the rear-side vertical wall portion (42) are made of casting or high-strength resin, and the hinge-reinforcement member (55) and the latch-reinforcement member (54) are configured to have higher ductility than the front-side vertical wall portion (41) and the rear-side vertical wall portion (42) and connected to the impact bar (46).