Eucithara striatissima is a small sea snail, a marine gastropod mollusk in the family Mangeliidae.

It is densely encircled by spiral threads, of which there are about forty on the body whorl.

About nineteen radials are projecting as tubercles along the angle of the shoulder, but faint above and below.

The whole surface has a secondary sculpture of close microscopic radial threads.

The aperture is incomplete, but commencing to form a varix and mounting on the preceding whorl.