The utility model relates to an automobile back position light and a taillight and an automobile with the same. An optical element of the position light comprises a light-emitting diode (LED) and at least one light guide. The LED, as a lighting source of the position light, is arranged at a light guide inlet of the light guide. According to the arrangement, the LED of the position light is high in brightness, low in heat, small in power consumption and capable of effectively reducing installation space. In addition, the light guide technology can effectively achieve even distribution of light of the LED so that using of the LED is reduced and a using rate of the light source is improved.