Sacabambaspis is an extinct genus of armored jawless fish which lived in the Ordovician period. Sacabambaspis inhabited shallow waters on the continental margins of the southern supercontinent Gondwana. The most complete specimens have been found in Bolivia, while armor fragments are also known from Argentina, Australia, and Oman. Sacabambaspis vaguely resembles a slender tadpole, with an oversized armor-plated head, flat body, and no discernible fins outside of its narrow tail. The eyes are closely spaced and positioned at the very front of the head, akin to car headlamps. It was about 35 cm (13+3⁄4 inches) long in total, including its distinctively thin scaly tail.

With many well-preserved specimens, Sacabambaspis is the best-known member of Arandaspida, a group of jawless fish found only in the Ordovician of Gondwana. Arandaspids were among the earliest members of the class Pteraspidomorpha, alongside a far more diverse group of jawless fish, the Silurian–Devonian heterostracans.

Sacabambaspis is named after the village of Sacabamba, Cochabamba Department, Bolivia, where the first fossils of the genus were found. S. janvieri, the type species of the genus, is known from the Anzaldo Formation of Bolivia.

Sacabambaspis janvieri was first described by Gagnier, Blieck & Rodrico (1986), based on a few armor fragments. Further discoveries in the late 1980s and early 1990s greatly expanded the list of specimens. Later studies in the mid-2000s cleared up a few remaining points of ambiguity regarding its armor structure and tail anatomy.

Over 30 specimens have been found in Bolivia, all crammed into a very confined area. Their close arrangement is believed to be the result of a fish kill, probably due a sudden inflow of fresh water and sediments from a large storm. They were found associated with a large number of lingulid brachiopods, also killed at the same time.

Indeterminate specimens (described as "Sacabambaspis sp.") have been found in many countries corresponding to the margin of Gondwana. Young (1997) described fossils of the genus from the Stokes Siltstone and Carmichael Sandstone of Central Australia. Specimens have also been reported from Argentina.

Sansom et al. (2009) described specimens from the Amdeh Formation of Oman on the Arabian Peninsula. The Oman discoveries showed that the fish were present all around the periphery of the ancient continent of Gondwana, and not just in the southern regions as had previously been shown by the findings from South America and Australia. The layers in Oman containing Sacabambaspis may be as old as the late Dapingian or early Darriwilian stages of the Middle Ordovician (roughly 470 million years ago). By comparison, the South American and Australian fossils are equivalent to the historical Llanvirn–Caradoc series (late Darriwilian to early Sandbian stages), persisting into the Late Ordovician (roughly 458 million years ago).

A Sacabambaspis model exhibited at the Natural History Museum of Helsinki in Finland became a source of internet memes and fan art in June 2023, following a viral tweet from August 2022. The Helsinki model of Sacabambaspis (サカバンバスピス) is a particularly popular subject in Japan, where it receives a level of attention akin to yuru-kyara (cute promotional mascots).