Lethata optima is a moth of the family Depressariidae.

The forewings are greyish overcast with reddish brown especially in the anal area and with the costa narrowly ochreous.

The termen is ochreous with a purplish spot at the end of the cell with scattered white scales.

The entire wing with scattered fuscous scales.

This article on a moth of the subfamily Stenomatinae is a stub.