Cosmocampus heraldi is a species of marine fish of the family Syngnathidae.

It is known from only seven specimens, which were found at the Desventuradas and Juan Fernandez Islands in Chile.

[1] It inhabits rocky reefs and sandy areas at depths of 6–23 metres (20–75 ft), where it can grow to lengths of 7 centimetres (2.8 in).

[1] This species is ovoviviparous, with males carrying eggs until giving birth to live young.

[2] Described by Ronald Alan Fritzsche, the specific name honours the ichthyologist Earl Stannard Herald (1914-1973) who had a lifelong interest in pipefish.