To enable a driver of an automobile to immediately know on which side the automobile has its filler port.

An automobile filler-port sign is provided at a position that a driver of an automobile easily finds to indicate on which side the automobile has its filler port. The filler-port sign is made of a seal 2 printed with an arrow, which permits its production at lower costs and a driver to stick it at a desired position. The seal 2 preferably has thereon a notation of the words 'filler port' or of a schematic drawing indicative of it. The seal 2 is stuck at a position that a driver in the front part of the interior of an automobile easily finds, such as on a dashboard 1, a windshield 3 and an instrument luster 4 around the driver's seat. The seal 2 may use a phosphor or luminosity in its chromatic parts to improve its visibility at night.