A speaker disposition structure of a vehicle, the speaker disposition structure comprising: a hinge pillar extending in a vehicle up-down direction; a side sill fixed to a lower end of the hinge pillar and extending in a vehicle front-rear direction; a speaker box that holds a speaker and is fixed to the hinge pillar in a vicinity of the side sill ; and a gap (S1) for arranging a vehicle component at an upper part of a vehicle-interior side of the side sill , the speaker box includes: an outer-box part ; an abutting part abutting the hinge pillar ; an upper space forming portion (S3) that bulges inward in a vehicle width direction from the abutting part above the gap (S1) and that holds the speaker ; and an extended space forming portion (S4) that extends downward from the upper space forming portion (S3) and is adjacent to a vehicle-width-direction inner side of the gap (S1), wherein the upper space forming portion (S3) and the extended space forming portion (S4) are arranged next to one another in an up-down direction and together confine a closed space (S5), and the extended space forming portion (S4) is formed such that a vehicle-width-direction dimension in a cross section orthogonal to the vehicle front-rear direction is smaller in a lower portion of the extended space forming portion (S4) than in an upper space forming portion (S3) of the extended space forming portion (S4), a first opening is formed at an inner wall of an hinge pillar inner , preferably at a middle portion in the up-down direction of the hinge pillar inner , and a second opening for attaching the outer-side box part of the speaker box is formed at a lower portion of the inner wall below the first opening . a hinge pillar extending in a vehicle up-down direction; a side sill fixed to a lower end of the hinge pillar and extending in a vehicle front-rear direction; a speaker box that holds a speaker and is fixed to the hinge pillar in a vicinity of the side sill ; and a gap (S1) for arranging a vehicle component at an upper part of a vehicle-interior side of the side sill , the speaker box includes: an outer-box part ; an abutting part abutting the hinge pillar ; an upper space forming portion (S3) that bulges inward in a vehicle width direction from the abutting part above the gap (S1) and that holds the speaker ; and an extended space forming portion (S4) that extends downward from the upper space forming portion (S3) and is adjacent to a vehicle-width-direction inner side of the gap (S1), an outer-box part ; an abutting part abutting the hinge pillar ; an upper space forming portion (S3) that bulges inward in a vehicle width direction from the abutting part above the gap (S1) and that holds the speaker ; and an extended space forming portion (S4) that extends downward from the upper space forming portion (S3) and is adjacent to a vehicle-width-direction inner side of the gap (S1), wherein the upper space forming portion (S3) and the extended space forming portion (S4) are arranged next to one another in an up-down direction and together confine a closed space (S5), and the extended space forming portion (S4) is formed such that a vehicle-width-direction dimension in a cross section orthogonal to the vehicle front-rear direction is smaller in a lower portion of the extended space forming portion (S4) than in an upper space forming portion (S3) of the extended space forming portion (S4), a first opening is formed at an inner wall of an hinge pillar inner , preferably at a middle portion in the up-down direction of the hinge pillar inner , and a second opening for attaching the outer-side box part of the speaker box is formed at a lower portion of the inner wall below the first opening . <EOS>