Phomopsis is a genus of ascomycete fungi in the family Diaporthaceae. It was previously in the Valsaceae family.

680 records are listed by Species Fungorum;

See List of Phomopsis species (for full list of species).

Selected species list includes;

Formerly placed here:

One of the species of this genus, P. viticola, cause a grape disease called Phomopsis or dead-arm. Usually, infections begin during early growth stages in spring. This affects leaves, fruit, rachises, and shoots of a plant.

This disease causes the formation of lesions on shoots, leaves, and rachises, but also can cause fruit rot.

It causes significant economic damage to grape vines.