A vehicular lamp including, within its lamp chamber, a reflector 14, a led 20 disposed behind the reflector 14 and a mushroom-shaped light guide 30 that extends coaxially with the led 20 and guides light emitted from the led 20 to the reflector 14. The light guide 30 has an umbrella portion 40 at its front end and a plane of incidence 33, which guides light from the led 20 into the light guide 30, at its rear end. The umbrella portion 40 has a first light emitting surface 42 for emitting light guided into the light guide 30 in the forward direction, reflection surfaces 44 and 46 for internally reflecting the guided light in the rearward direction and radially outward direction, and a second light emitting surface 48 for emitting the internally reflected light toward the reflector 14.