Emydocephalus orarius, also known as the white-crowned sea snake or white-naped sea snake, is a species of elapid sea snake endemic to Australian waters.

The specific epithet orarius (“coastal”) refers to its known habitat.

[2] The species grows up to 116 cm in length.

[2] The species has been recorded from soft-bottomed waters off the Kimberley, Pilbara and Gascoyne coasts of Western Australia, including Barrow, and Legendre Islands.

The type locality is Shark Bay.