Dichomeris cuspis is a moth in the Gelechiidae family. It was described by Park in 1994. It is found in south-eastern Siberia, Korea and China (Shaanxi). The length of the forewings is 7.2-7.7 mm. The forewings are uniform dark fuscous, shining blue leaden-metallic with a dash-shaped yellowish-white strigula at three-fourth on the anterior margin. The hindwings are dark grey. The larvae feed on Quercus acuteserrata.