Disc brake disc arranged around a rotational axis (A-A), comprising: - a braking band extended around said rotational axis (A-A) and forming two opposite braking surfaces (28, 29) suitable to cooperate with brake caliper pads, arranged astride said braking band; - said disc defining an axial direction (A-A) coincident or parallel to said rotational axis (A-A), a radial direction (R-R) defining a radially external direction when moving away from said axial direction, as well as a radially internal direction when approaching said axial direction (A-A), as well as a circumferential direction (T-T) orthogonal to said axial direction (A-A) and said radial direction (R-R); - said disc further comprising a drum; - said drum comprising a connection flange, having a connection portion suitable to connect the drum to a support hub onto which a rim of a vehicle wheel is connected; - said connection portion of said connection flange comprising a surface facing the hub and an opposite surface facing the wheel rim; - said surface facing the hub comprising a housing suitable to accommodate a portion of the hub; - said drum further comprising an edge arranged radially outside said portion for connecting the drum to the hub; - said edge being arranged radially outside said housing suitable to accommodate the hub; - said drum further comprising a drum body connecting said edge to the braking band; - said drum body delimiting an outer space comprised between the drum and the wheel rim; - said drum body being suitable to create an interspace between the drum and the hub accommodated therein, said interspace axially traversing, according to the axial direction (A-A), substantially the entire drum until it reaches said edge; - wherein said edge delimits at least one opening which puts into communication the interspace provided between the drum body and the hub with the external of the drum; - said at least one opening being arranged radially outside said housing for the hub; - and wherein said at least one opening is delimited by walls having at least one section inclined with respect to the axial direction (A-A), avoiding that said opening extends as a channel in the drum body. - a braking band extended around said rotational axis (A-A) and forming two opposite braking surfaces (28, 29) suitable to cooperate with brake caliper pads, arranged astride said braking band; - said disc defining an axial direction (A-A) coincident or parallel to said rotational axis (A-A), a radial direction (R-R) defining a radially external direction when moving away from said axial direction, as well as a radially internal direction when approaching said axial direction (A-A), as well as a circumferential direction (T-T) orthogonal to said axial direction (A-A) and said radial direction (R-R); - said disc further comprising a drum; - said drum comprising a connection flange, having a connection portion suitable to connect the drum to a support hub onto which a rim of a vehicle wheel is connected; - said connection portion of said connection flange comprising a surface facing the hub and an opposite surface facing the wheel rim; - said surface facing the hub comprising a housing suitable to accommodate a portion of the hub; - said drum further comprising an edge arranged radially outside said portion for connecting the drum to the hub; - said edge being arranged radially outside said housing suitable to accommodate the hub; - said drum further comprising a drum body connecting said edge to the braking band; - said drum body delimiting an outer space comprised between the drum and the wheel rim; - said drum body being suitable to create an interspace between the drum and the hub accommodated therein, said interspace axially traversing, according to the axial direction (A-A), substantially the entire drum until it reaches said edge; - wherein said edge delimits at least one opening which puts into communication the interspace provided between the drum body and the hub with the external of the drum; - said at least one opening being arranged radially outside said housing for the hub; - and wherein said at least one opening is delimited by walls having at least one section inclined with respect to the axial direction (A-A), avoiding that said opening extends as a channel in the drum body.