Dichomeris plasticus is a moth in the Gelechiidae family. It was described by Meyrick in 1904. It is found in Australia, where it has been recorded from New South Wales. The wingspan is 16-18 mm. The forewings are yellow-ochreous, sprinkled with fuscous, with the plical and second discal stigmata small, obscure, dark fuscous. There is a small suffused dark fuscous spot before the tornus. The hindwings are grey, but darker posteriorly.