Most reports of neoplasia in bats are in captive Egyptian fruit bats (Rousettus aegyptiacus), a megachiropteran species. Only three reports of neoplasia in microchiropteran species have been reported. We report the detection of a tumor in a wild brown long-eared bat (Plecotus auritus), a microchiropteran species, in England. Histolopathology indicated the mass was a spindle cell tumor, likely of smooth muscle origin, which was confirmed by immunohistochemistry.