Anthoceras is a genus of straight, annulated, proterocamerioceratid molluscs (Order Endocerida) from the Lower Ordovician, found in North America, North-Western Australia, and Siberia.

The cross section is circular, the siphuncle moderately large, and marginal.

Segments are constricted (producing concave profiles in internal molds); septal necks hemichoantici to subholochoantic (reaching halfway to almost to the previous septum); connecting rings thick.

This genus is based on the phragmocone, the chambered part of the shell; the apical and apertural ends are unknown.

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