Ascarosepion novaehollandiae is a species of cuttlefish native to the southern Indo-Pacific. Its natural range stretches from Shellharbour, New South Wales (34°35′S 150°52′E) to Northwest Shelf in Western Australia (18°57′S 118°45′E). It lives at depths of between 15 and 348 m.

Description The type specimen was collected off Kangaroo Island, South Australia (35°50′S 138°03′E). It is deposited at the Muséum National d'Histoire Naturelle in Paris. The species was described by Hoyle in 1909. Ascarosepion novaehollandiae is known to grow to a mantle length of 77 mm, but specimens from Spencer Gulf reach mantle lengths of around 125 mm and larger specimens of cuttlebones reaching lengths of 170 mm have also been found.

Spencer Gulf population Specimens collected from Spencer Gulf in South Australia have mantle lengths and weights "rarely exceeding" 125 mm and 521 grams respectively. The mantle is oblong with narrow lateral fins running along its length. Specimens are brown, with small white blotches speckled on the mantle.