Eudonia trivirgatus is a moth in the family Crambidae.

The forewings are whitish ochreous, the veins lined with white.

There is a blackish-fuscous median streak from the base to the apex, interrupted by a narrow bar before the middle.

There is also a blackish-fuscous longitudinal wedge-shaped mark above the anal angle and usually a hindmarginal row of cloudy blackish dots.

Adults have been recorded on wing in December, February and March.