Dichomeris leucocosma is a moth in the Gelechiidae family. It was described by Meyrick in 1916. It is found in Malawi. The wingspan is about 11 mm. The forewings are pale lilac-grey irregularly mixed with dark fuscous, especially posteriorly. There is a narrow suffused ochreous-white costal streak from the base, broadest at the base, terminating in a triangular ochreous-white patch at two-thirds reaching half across the wing. There is a white dot representing the plical stigma. The hindwings are grey.