A lighting device for a vehicle includes a light source device; a main lens; a reflective fluorescent body configured to reflect and convert wavelengths of incident beams; and a prism arranged between the main lens and the reflective fluorescent body. The prism is configured to: reflect beams emitted from the light source device to be incident on the reflective fluorescent body; and transmit, through the prism and to the main lens, beams reflected from the reflective fluorescent body. The prism includes: a first surface facing the reflective fluorescent body; a second surface through which beams are incident; and a third surface forming an acute angle with the first surface. The prism is configured such that the beams incident through the second surface of the prism form angles of incidence, with respect to the third surface of the prism, that are greater than a critical angle of the prism.