Diagnosis. Shell small, broadly fusiform, with tall turreted spire and long straight canal; spire little shorter than height of aperture plus canal; with eight whorls, including a large conical protoconch of six whorls , the first whorl smooth, remainder axially costate. Color uniformly buff.
Description. Shell small, 8.2 mm in height, broadly fusiform; spire tall, turreted, slightly shorter than height of aperture plus canal; with eight whorls, including large conical protoconch of six whorls, first whorl smooth, other whorls axially costate. Spire whorls sculptured firstly with strongly crested subsutural fold, composed of two closely spaced cords, first one lower than second, about three crisp spirals on concave shoulder area, then prominent, gemmate, bicarinate peripheral keel, also composed of two closely spaced cords, about 20 vertically fused gemmules on penultimate whorl. Upper base with three strong spaced primary cords, neck and anterior end with about 11 spaced threads. Outer lip broken, inner lip smooth, columella with distinct trace of elongated spiral folds, anterior canal moderately long, notched. Color uniformly buff.

Gemmula grandigyrata sp. nov. can be easily distinguished from all other known species of the genus Gemmula by the large conical protoconch with 6 whorls, a peculiar structure in the genus Gemmula.