Olbiaspididae is a family of extinct amphiaspidid heterostracan agnathans whose fossils are restricted to Lower Devonian marine strata of Siberia near the Taimyr Peninsula.

Amphiaspids are easily distinguished from other heterostracans in that all of the plates of the cephalothoracic armor are fused into a single, muff-like unit, so that the forebody of the living animal would have looked, in the case of olbiaspidids, vaguely like a hot water bottle with a pair of small, or degenerated eyes, with each flanked by a preorbital opening, and a simple, slit-like mouth positioned at the anteriormost portion of the cephalothoracic armor.

O. coalescens resembles a hot water bottle with dorso-anteriorly positioned small eyes flanked by preorbital openings, and a prominent dorsal spine, while O. latissima is extremely broad in comparison.

Kureykaspis salebrosa has a compact cephalothoracic armor that is pear-shaped (when viewed from above), and that is decorated with distinctive ridges and nodules.

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