Grapevine trunk diseases have become one of the main threats to grape production worldwide, with
Diaporthe
species as an emerging group of pathogens in China. At present, relatively little is known about the taxonomy and genetic diversity of Chinese
Diaporthe
populations, including their relationships to other populations worldwide. Here, we conducted an extensive field survey in six provinces in China to identify and characterize
Diaporthe
species in grape vineyards. Ninety-four isolates were identified and analyzed using multi-locus phylogeny. The isolates belonged to eight species, including three novel taxa,
Diaporthe guangxiensis (D. guangxiensis), Diaporthe hubeiensis (D. hubeiensis), Diaporthe viniferae (D. viniferae)
, and three new host records,
Diaporthe gulyae (D. gulyae), Diaporthe pescicola (D. pescicola)
, and
Diaporthe unshiuensis (D. unshiuensis)
. The most commonly isolated species was
Diaporthe eres (D. eres)
. In addition, high genetic diversity was observed for
D. eres
in Chinese vineyards. Haplotype network analysis of
D. eres
isolates from China and Europe showed a close relationship between samples from the two geographical locations and evidence for recombination. In comparative pathogenicity testing,
D. gulyae
was the most aggressive taxon, whereas
D. hubeiensis
was the least aggressive. This study provides new insights into the
Diaporthe
species associated with grapevines in China, and our results can be used to develop effective disease management strategies.