Lepetella sierrai is a species of sea snail, a marine gastropod mollusk in the family Lepetellidae.
This species is the host of the ectoparasitic copepod Lepetellicola brescianii <small>Huys, Lopez Gonzalez, Roldan & Luque, 2002</small>
The shell grows to a size of 2.5 mm.
This marine species occurs from the Bay of Biscay to Madeira.