Cremnoceramus ("cremno-" = kremnos [Greek]: precipice or over hanging wall or bank; "ceramus" = keramos [Greek]: clay pot) is an extinct genus of fossil marine pteriomorphian bivalves that superficially resembled the related winged pearly oysters of the extant genus Pteria.

[2][3] Cremnoceramus were facultatively mobile, blind, suspension feeding bivalves with low-magnesium calcite shells.

[3] Inoceramids, like the Cremnoceramus in particular, had thick shells composed of particular "prisms" of calcite deposited perpendicular to the surface, and unweathered fossils commonly preserve the mother-of-pearl luster the shells had in life.

[4] Compared to the many examples of broad and flattened Inoceramidae, Cremnoceramus shells are rather "high-walled", deep bowl-shaped.

Fossils of the genus have been found in:[6] Note the oyster encrustation of the top shells: This article about a Cretaceous animal is a stub.