A vehicle lighting unit comprising: a first light source; a light guiding lens provided forward of the first light source, configured to project light emitted from the first light source forward to form a high beam or a low beam; characterized by a DRL unit including a second light source, configured to function as a daytime running lamp, the light guiding lens including: a front surface; a rear surface; a light incident surface located in front of the first light source, configured to allow the light emitted from the first light source to enter the light guiding lens therethrough; a front reflection surface formed in the front surface, located in front of the light incident surface, the front reflection surface configured to internally reflect the light having entered the light guiding lens through the light incident surface to a direction obliquely rearward and toward a first side with respect to an approximately perpendicular direction to a front-rear direction; a rear reflection surface formed in the rear surface, located at a portion of the rear surface in the direction obliquely rearward and toward the first side with respect to the front reflection surface, the rear reflection surface configured to internally and forwardly reflect the light having been reflected by the front reflection surface; a light exiting surface formed in the front surface, located in front of the rear reflection surface, the light exiting surface configured to allow the light having been reflected by the rear reflection surface forward to be projected; and a light-transmitting section, formed in the front surface, located between the front reflection surface and the rear reflection surface in terms of the perpendicular direction, the light-transmitting section configured to allow light to pass therethrough in the front-rear direction, the DRL unit being disposed in the rear of the light-transmitting section of the light guiding lens so that the light emitted from the second light source can be projected forward while allowing the light to pass through the light-transmitting section. a first light source; a light guiding lens provided forward of the first light source, configured to project light emitted from the first light source forward to form a high beam or a low beam; characterized by a DRL unit including a second light source, configured to function as a daytime running lamp, the light guiding lens including: a front surface; a rear surface; a light incident surface located in front of the first light source, configured to allow the light emitted from the first light source to enter the light guiding lens therethrough; a front reflection surface formed in the front surface, located in front of the light incident surface, the front reflection surface configured to internally reflect the light having entered the light guiding lens through the light incident surface to a direction obliquely rearward and toward a first side with respect to an approximately perpendicular direction to a front-rear direction; a rear reflection surface formed in the rear surface, located at a portion of the rear surface in the direction obliquely rearward and toward the first side with respect to the front reflection surface, the rear reflection surface configured to internally and forwardly reflect the light having been reflected by the front reflection surface; a light exiting surface formed in the front surface, located in front of the rear reflection surface, the light exiting surface configured to allow the light having been reflected by the rear reflection surface forward to be projected; and a light-transmitting section, formed in the front surface, located between the front reflection surface and the rear reflection surface in terms of the perpendicular direction, the light-transmitting section configured to allow light to pass therethrough in the front-rear direction, a front surface; a rear surface; a light incident surface located in front of the first light source, configured to allow the light emitted from the first light source to enter the light guiding lens therethrough; a front reflection surface formed in the front surface, located in front of the light incident surface, the front reflection surface configured to internally reflect the light having entered the light guiding lens through the light incident surface to a direction obliquely rearward and toward a first side with respect to an approximately perpendicular direction to a front-rear direction; a rear reflection surface formed in the rear surface, located at a portion of the rear surface in the direction obliquely rearward and toward the first side with respect to the front reflection surface, the rear reflection surface configured to internally and forwardly reflect the light having been reflected by the front reflection surface; a light exiting surface formed in the front surface, located in front of the rear reflection surface, the light exiting surface configured to allow the light having been reflected by the rear reflection surface forward to be projected; and a light-transmitting section, formed in the front surface, located between the front reflection surface and the rear reflection surface in terms of the perpendicular direction, the light-transmitting section configured to allow light to pass therethrough in the front-rear direction, the DRL unit being disposed in the rear of the light-transmitting section of the light guiding lens so that the light emitted from the second light source can be projected forward while allowing the light to pass through the light-transmitting section.