A vehicular cooling device, comprising: a housing; an opening through which outside air flows into the housing in which a cooling target is housed, the opening being formed in, among surfaces of the housing, a surface intended to be parallel to a travelling direction of a vehicle provided with the housing; a discharge port through which the outside air is discharged, formed in a surface of the housing; an air channel formed inside the housing and including one end connected to the opening and another end connected to the discharge port; and a fan provided inside the air channel to supply to the cooling target the outside air that flows through the opening into the air channel and discharge through the discharge port the outside air that has undergone heat exchange with the cooling target, characterized in that the vehicular cooling device comprises first blockers spaced apart in the travelling direction in the opening; and third blockers provided in the opening at positions to block a flow path of the outside air that flows through the first blockers toward the air channel, the third blockers being spaced apart in the travelling direction, wherein each of the first blockers extends in a direction perpendicular to both of the travelling direction and an inflow direction of the outside air, and includes a first member and a second member, the first member being a plate-like member having a main surface intersecting the travelling direction, the first member and the second member of each of the first blockers being symmetric with respect to a plane perpendicular to the travelling direction and having a travelling-direction spacing therebetween that increases along the inflow direction of the outside air, wherein each of the third blockers extends in the direction perpendicular to both of the travelling direction and the inflow direction of the outside air, and includes a third member and a fourth member, the third member being a plate-like member having a main surface intersecting the travelling direction, the third member and the fourth member of each of the third blockers being symmetric with respect to a plane perpendicular to the travelling direction and having a travelling-direction spacing therebetween that decreases along the inflow direction of the outside air, and wherein a surface of the opening located when in use on a vertically lower side thereof includes, in a region between the third member and the fourth member, a hole through which foreign objects contained in the outside air that flows into the opening are discharged. a housing; an opening through which outside air flows into the housing in which a cooling target is housed, the opening being formed in, among surfaces of the housing, a surface intended to be parallel to a travelling direction of a vehicle provided with the housing; a discharge port through which the outside air is discharged, formed in a surface of the housing; an air channel formed inside the housing and including one end connected to the opening and another end connected to the discharge port; and a fan provided inside the air channel to supply to the cooling target the outside air that flows through the opening into the air channel and discharge through the discharge port the outside air that has undergone heat exchange with the cooling target, characterized in that the vehicular cooling device comprises first blockers spaced apart in the travelling direction in the opening; and third blockers provided in the opening at positions to block a flow path of the outside air that flows through the first blockers toward the air channel, the third blockers being spaced apart in the travelling direction, wherein each of the first blockers extends in a direction perpendicular to both of the travelling direction and an inflow direction of the outside air, and includes a first member and a second member, the first member being a plate-like member having a main surface intersecting the travelling direction, the first member and the second member of each of the first blockers being symmetric with respect to a plane perpendicular to the travelling direction and having a travelling-direction spacing therebetween that increases along the inflow direction of the outside air, wherein each of the third blockers extends in the direction perpendicular to both of the travelling direction and the inflow direction of the outside air, and includes a third member and a fourth member, the third member being a plate-like member having a main surface intersecting the travelling direction, the third member and the fourth member of each of the third blockers being symmetric with respect to a plane perpendicular to the travelling direction and having a travelling-direction spacing therebetween that decreases along the inflow direction of the outside air, and wherein a surface of the opening located when in use on a vertically lower side thereof includes, in a region between the third member and the fourth member, a hole through which foreign objects contained in the outside air that flows into the opening are discharged.