Ceramium nodulosum is a small red marine alga.

[1] Ceramium nodulosum is a small filamentous branching alga growing to a height of 30 cm in tufts of erect branches usually fully corticate.

The apices of main axes are straight or slightly curled inward at the tips.

The axes and branches are usually fully corticate and, unlike some other species, it is without spines.

[1] The species Ceramium virgatum Roth is noted as a possible synonym elsewhere.