A vehicle lamp configured such that the distribution of light from a light source is controlled by an optical member, the vehicle lamp comprising: a housing configured to support the optical member pivotably around a pivotal axis extending in a first direction intersecting a front and rear direction of the lamp; and an optical axis adjustment screw configured to pivot the optical member around the pivotal axis with respect to the housing, wherein the optical axis adjustment screw is supported by the housing in a state of being arranged to extend in a second direction intersecting the first direction and the front and rear direction of the lamp, wherein a protruding piece extending toward the rear of the lamp is formed at an end portion of the optical member in the first direction, wherein a groove portion (1134Ba1) to be screwed with the optical axis adjustment screw is formed on an inner surface of a rear region of the protruding piece located on the rear side of the lamp with respect to the pivotal axis, and wherein a detachment preventing portion (1012b2) is formed in the housing in a positional relationship in close proximity to an outer surface of the rear region of the protruding piece so as to prevent the groove portion (1134Ba1) of the protruding piece from being disengaged from the screwed state with the optical axis adjustment screw, characterised in that a gap is defined between the detachment preventing portion (1012b2) and the outer surface of the rear region of the protruding piece, wherein the gap is smaller than an effective teeth depth defined in the screwed state between the groove portion (1134Ba1) of the rear region of the protruding piece and a threaded portion of the optical axis adjustment screw. a housing configured to support the optical member pivotably around a pivotal axis extending in a first direction intersecting a front and rear direction of the lamp; and an optical axis adjustment screw configured to pivot the optical member around the pivotal axis with respect to the housing, wherein the optical axis adjustment screw is supported by the housing in a state of being arranged to extend in a second direction intersecting the first direction and the front and rear direction of the lamp, wherein a protruding piece extending toward the rear of the lamp is formed at an end portion of the optical member in the first direction, wherein a groove portion (1134Ba1) to be screwed with the optical axis adjustment screw is formed on an inner surface of a rear region of the protruding piece located on the rear side of the lamp with respect to the pivotal axis, and wherein a detachment preventing portion (1012b2) is formed in the housing in a positional relationship in close proximity to an outer surface of the rear region of the protruding piece so as to prevent the groove portion (1134Ba1) of the protruding piece from being disengaged from the screwed state with the optical axis adjustment screw, characterised in that a gap is defined between the detachment preventing portion (1012b2) and the outer surface of the rear region of the protruding piece, wherein the gap is smaller than an effective teeth depth defined in the screwed state between the groove portion (1134Ba1) of the rear region of the protruding piece and a threaded portion of the optical axis adjustment screw.