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The Gram-negative bacterium Haemophilus parasuis is the etiologic agent of Glässer’s disease in pigs, and causes significant economic losses to the swine industry. This bacterium has been classified as a member of the family Pasteurellaceae in the genus Haemophilus , but phylogenetic relatedness has not been adequately examined to support this genus classification. Phenotypically, all 38 strains of H. parasuis tested were positive for catalase activity, oxidase activity, V-factor requirement, and acid formation from maltose and d-galactose without gas. All strains were negative for X-factor requirement, formation of indole from tryptophan, urease, l-arabinose, and α-glucosidase activity. To determine whether H. parasuis belongs to one of the current Pasteurellaceae genera 40 H . parasuis genomes, plus those of representative Pasteurellaceae , were subjected to phylogenetic analysis of concatenated, multi-protein alignments. Sequence variation at 16S rRNA and rpoB loci allowed the 15 reference serovars of H. parasuis to be integrated into the whole-genome tree. The phylogenetic analysis showed H. parasuis to be a distinct and tight clade whose sister taxon is the genus Bibersteinia . Within H. parasuis two clades were identified with individual serovars distributed between the two. As a result, H. parasuis was confirmed as a member of the family Pasteurellaceae , but was distinct from other genera in this family. Therefore, we propose the name Glaesserella parasuis, gen. nov., comb. nov. for bacterial strains currently classified as H. parasuis . The reference strain of this species is ATCC 19417 (1374)T, NCTC 4557T, DSM 21448T, CCUG 3712T.