A vehicle-body structure of a vehicle, comprising: a vehicle-body frame member forming an opening portion for entrance at a vehicle side part; and a side door provided so as to open and/or close the opening portion, wherein the side door comprises a door panel portion and a reinforcement portion (71 to 74) provided at a peripheral part of the door panel portion such that the reinforcement portion (71 to 74) overlaps with the vehicle-body frame member in a vehicle side view, the reinforcement portion (71 to 74) being configured to reinforce the door panel portion such that when a collision load is inputted to the side door in a vehicle side collision, deformation of the peripheral part of the door panel portion is suppressed and/or a connection state of the door panel portion and the vehicle-body frame member is maintained, the vehicle-body frame member comprises a wall portion (12c, 13, 23c, 24, 34, 44c, 45) extending or expanding in a vehicle longitudinal direction and/or in a vertical direction at the opening portion, the wall portion (12c, 13, 23c, 24, 34, 44c, 45) includes a side-sill flange of a side sill, a side-sill side wall portion of a side-sill outer panel of the side sill, a hinge-pillar flange of a hinge pillar, a hinge-pillar side wall portion of a hinge-pillar outer panel of a hinge pillar, a center-pillar flange of a center pillar, a center-pillar side wall portion of the center pillar, and a roof-side flange of a roof-side outer panel of a roof side rail, and at least part of the peripheral part of the door panel portion is configured to overlap with the side-sill flange, the side-sill side wall portion, the hinge-pillar flange, the hinge-pillar side wall portion, the center-pillar flange, the center-pillar side wall portion, and the roof-side flange, in the vehicle side view, characterized in that the reinforcement portion (71 to 74) is provided to overlap with the side-sill flange, the side-sill side wall portion, the hinge-pillar flange, the hinge-pillar side wall portion, the center-pillar flange, the center-pillar side wall portion, and the roof-side flange, in the vehicle side view. a vehicle-body frame member forming an opening portion for entrance at a vehicle side part; and a side door provided so as to open and/or close the opening portion, wherein the side door comprises a door panel portion and a reinforcement portion (71 to 74) provided at a peripheral part of the door panel portion such that the reinforcement portion (71 to 74) overlaps with the vehicle-body frame member in a vehicle side view, the reinforcement portion (71 to 74) being configured to reinforce the door panel portion such that when a collision load is inputted to the side door in a vehicle side collision, deformation of the peripheral part of the door panel portion is suppressed and/or a connection state of the door panel portion and the vehicle-body frame member is maintained, the vehicle-body frame member comprises a wall portion (12c, 13, 23c, 24, 34, 44c, 45) extending or expanding in a vehicle longitudinal direction and/or in a vertical direction at the opening portion, the wall portion (12c, 13, 23c, 24, 34, 44c, 45) includes a side-sill flange of a side sill, a side-sill side wall portion of a side-sill outer panel of the side sill, a hinge-pillar flange of a hinge pillar, a hinge-pillar side wall portion of a hinge-pillar outer panel of a hinge pillar, a center-pillar flange of a center pillar, a center-pillar side wall portion of the center pillar, and a roof-side flange of a roof-side outer panel of a roof side rail, and at least part of the peripheral part of the door panel portion is configured to overlap with the side-sill flange, the side-sill side wall portion, the hinge-pillar flange, the hinge-pillar side wall portion, the center-pillar flange, the center-pillar side wall portion, and the roof-side flange, in the vehicle side view, characterized in that the reinforcement portion (71 to 74) is provided to overlap with the side-sill flange, the side-sill side wall portion, the hinge-pillar flange, the hinge-pillar side wall portion, the center-pillar flange, the center-pillar side wall portion, and the roof-side flange, in the vehicle side view.