Aristotelia sinistra is a moth of 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 10-12 mm. The forewings are ashy-fuscous, purplish-tinged, sometimes irrorated with dark fuscous and with the markings blackish mixed with deep golden-bronzy. There is an obsolete dorsal spot near the base and a subcostal spot at one-sixth, and one on the fold slightly beyond it. An outwardly oblique bar is found from beneath the costa at one-third to the fold and a spot in the middle of the disc, and one at two-thirds (representing the stigmata). There are also indistinct opposite costal and tornal whitish spots at two-thirds. The hindwings are grey.