Hartog Plate or Dirk Hartog's Plate is either of two pewter plates, although primarily the first, which were left on Dirk Hartog Island during a period of European exploration of the western coast of Australia prior to European settlement there. The first plate, left in 1616 by Dutch explorer Dirk Hartog, is the oldest-known artifact of European exploration in Australia still in existence. A replacement, copying the text of the original plus some new text, was left in 1697 – the original dish returned to the Netherlands, where it is on display in the Rijksmuseum. Further additions at the site, in 1801 and 1818, led to the location being named Cape Inscription.

Dirk Hartog Island is an island off the Gascoyne coast of Western Australia, within the Shark Bay World Heritage Area. It is about 80 kilometres long and between 3 and 15 kilometres wide and is Western Australia's largest and most western island. It covers an area of 620 square kilometres and is approximately 850 kilometres north of Perth.