A light guiding lens configured to project light in a light-irradiating direction, the light guiding lens comprising: an incident portion configured to receive light emitted from a light source (21, 22) so that the light can enter the light guiding lens; and a light guiding portion having a rear end portion and a front surface portion, the light guiding portion being configured to guide the light entering through the incident portion to cause the light to exit through the front surface portion, the light guiding lens being extended from the rear end portion to the front surface portion in the light-irradiation direction and also in a second direction crossing the light-irradiation direction, wherein the incident portion is provided at the rear end portion of the light guiding portion to be erected therefrom, the incident portion includes an incident surface that is disposed at one longitudinal end portion of the incident portion on one end side and configured to receive light from the light source to cause the light to enter the incident portion and to be in parallel to a direction in which the incident portion is erected, the light guiding portion includes a longitudinal end portion projected more than the one longitudinal end portion of the incident portion in the second direction and having a side end surface with the light guiding portion being gradually widened from the rear end portion to the front surface portion including the longitudinal end portion, the light guiding portion further includes a reflection surface at the rear end portion to be opposite to the incident surface, the reflection surface being configured to internally reflect light entering through the incident surface and guided through the incident portion to the side end surface of the longitudinal end portion, and the side end surface includes a plurality of lens cuts formed therein, so that the lens cuts internally reflect the light having been internally reflected by the reflection surface to the front surface portion; the light guiding lens being characterized in that the side end surface is formed to have a front side end surface projected sharply in the second direction more than the remaining side end surface, and the front surface portion of the light guiding portion includes a side end front surface positioned in front of the front side end surface of the side end surface, and the side end front surface includes a plurality of second lens cuts configured to forwardly refract the light having been internally reflected by the reflection surface. an incident portion configured to receive light emitted from a light source (21, 22) so that the light can enter the light guiding lens; and a light guiding portion having a rear end portion and a front surface portion, the light guiding portion being configured to guide the light entering through the incident portion to cause the light to exit through the front surface portion, the light guiding lens being extended from the rear end portion to the front surface portion in the light-irradiation direction and also in a second direction crossing the light-irradiation direction, wherein the incident portion is provided at the rear end portion of the light guiding portion to be erected therefrom, the incident portion includes an incident surface that is disposed at one longitudinal end portion of the incident portion on one end side and configured to receive light from the light source to cause the light to enter the incident portion and to be in parallel to a direction in which the incident portion is erected, the light guiding portion includes a longitudinal end portion projected more than the one longitudinal end portion of the incident portion in the second direction and having a side end surface with the light guiding portion being gradually widened from the rear end portion to the front surface portion including the longitudinal end portion, the light guiding portion further includes a reflection surface at the rear end portion to be opposite to the incident surface, the reflection surface being configured to internally reflect light entering through the incident surface and guided through the incident portion to the side end surface of the longitudinal end portion, and the side end surface includes a plurality of lens cuts formed therein, so that the lens cuts internally reflect the light having been internally reflected by the reflection surface to the front surface portion; the light guiding lens being characterized in that the side end surface is formed to have a front side end surface projected sharply in the second direction more than the remaining side end surface, and the front surface portion of the light guiding portion includes a side end front surface positioned in front of the front side end surface of the side end surface, and the side end front surface includes a plurality of second lens cuts configured to forwardly refract the light having been internally reflected by the reflection surface.