Kate Brown Stephens was an American naturalist and the curator of mollusks and marine invertebrates at the San Diego Natural History Museum from 1910 to 1936.

[1] Helping to raise her younger brother George while the family lived in the Kensington area of London, Kate is said to have worked at the Natural History Museum.

Her early field work included collecting butterflies, but her research interest area was shells and fossils, and she became known as the authority on terrestrial and marine mollusks of the San Diego region.

[5] Stephens accompanied her husband on many collecting trips in the early 1900s, including a four-month expedition in 1902 to the Colorado Desert for the U. S. Biological Survey.

Kate Stephens's field notes have been digitized by the San Diego Natural History Museum Research Library and are available on the Internet Archive.