Diachrysia chrysitis, the burnished brass, is a species of moth of the family Noctuidae.

It is found in Europe, the Caucasus, Russia, Russian Far East and Siberia.

Forewing brassy green; the basal patch and broad median fascia, widening at costa, purplish brown; subterminal line preceded by a shade showing deeper green in certain lights; the terminal area paler brown; the three stigmata with dark outlines; hindwing fuscous with the fringe pale; in the ab.

juncta Tutt the median fascia is more or less widely broken in the middle, the two brassy green areas becoming confluent; - in ab.

The larvae feed on various herbaceous plants, such as nettle, Lamium, thistles and oregano.