Polystira vibex is a species of sea snail, a marine gastropod mollusc in the family Turridae, the turrids.

The chief character which strikes one on comparing the P. vibex with P. albida is that the shell is surrounded with bands of olive-green color, polished, narrow and resident in the epidermis, but visible through the translucent shell in the aperture.

They extend only over the whorl, the pillar from its junction with the body is destitute of them, and, when fresh, is of a delicate rose color, which is apt to fade.

This white or rosy rostrum contrasts vividly with the striped body and spire.

P. vibex can be found in Caribbean waters, ranging from the eastern coast of Florida south to the Lesser Antilles.