Oligodon calamarius is a species of nonvenomous colubrid endemic to Sri Lanka.

Oligodon templetoni, now a junior synonym of Oligodon calamarius, was named in honour of Irish naturalist Dr. Robert Templeton who obtained the first known specimen.

[2][3] O. calamarius is a terrestrial snake from lowlands of the wet zone, reaching montane limits, up to 1,800 m (5,900 ft).

There are 18–24 narrow dark brown, light-edged cross-bands that are either complete or half-way cross the back.

The forehead has a dark crescentric marking and an elongated spot behind it.