Haemophilus
ducreyi - influenzae - parainfluenzae - pittmaniae

Hafnia
alvei

Hahella
ganghwensis

Halanaerobacter
chitinivorans - lacunarum - salinarius

Halanaerobium
acetethylicum - alcaliphilum - congolense - lacusrosei - praevalens - saccharolyticum

Haliangium
ochraceum - tepidum

Haliscomenobacter
hydrossis

Haloactinomyces
albus - sp.

Haloarcula
argentinensis - hispanica - japonica - marismortui - quadrata - sp. - vallismortis

Halobacillus
aidingensis - dabanensis - halophilus - karajensis - litoralis - locisalis - salinus - trueperi - yeomjeoni

Halobacterium
salinarum - sp.

Halobacteroides
elegans - halobius

Halobaculum
gomorrense

Halocella
cellulosilytica

Halochromatium
glycolicum - salexigens

Halococcus
acetoinfaciens - agglomeratus - dombrowskii - morrhuae - nondenitrificans - saccharolyticus - salifodinae

Haloferax
denitrificans - gibbonsii - lucentense - mediterranei - sulfurifontis - volcanii

Halogeometricum
borinquense

Halolactibacillus
halophilus - miurensis

Halomicrobium
mukohataei

Halomonas
alimentaria - anticariensis - aquamarina - axialensis - boliviensis - campaniensis - cupida - desiderata - elongata - eurihalina - halmophila - halocynthiae - halodenitrificans - halodurans - halophila - hydrothermalis - magadiensis - marisflavi - maura - meridiana - muralis - neptunia - pacifica - pantelleriensis - salina - sp. - subglaciescola - sulfidaeris - taeanensis - variabilis - ventosae - venusta

Halonatronum
saccharophilum

Halorhabdus
utahensis

Halorhodospira
abdelmalekii - halochloris - halophila - neutriphila

Halorubrum
coriense - lacusprofundi - saccharovorum - sodomense - tebenquichense - vacuolatum

Haloterrigena
thermotolerans - turkmenica

Halothermothrix
orenii

Halothiobacillus
halophilus - hydrothermalis - kellyi - neapolitanus

Helcococcus
kunzii - ovis - sueciensis

Helicobacter
cinaedi - fennelliae - pylori

Heliobacillus
mobilis

Heliobacterium
chlorum - gestii - modesticaldum - undosum

Heliophilum
fasciatum

Heliorestis
baculata

Herbaspirillum
autotrophicum - frisingense - huttiense - rubrisubalbicans - seropedicae - sp.

Herbidospora
cretacea

Herminiimonas
aquatilis - arsenicoxydans - fonticola

Herpetosiphon
aurantiacus - geysericola - sp.

Hespellia
porcina - stercorisuis

Hippea
maritima

Hirschia
baltica

Hoeflea
marina

Holdemania
filiformis

Holophaga
foetida

Hongiella
mannitolivorans - marincola - ornithinivorans

Hyalangium
minutum

Hydrocarboniphaga
effusa

Hydrogenivirga
caldilitoris

Hydrogenobacter
hydrogenophilus - thermophilus

Hydrogenobaculum
acidophilum

Hydrogenophaga
atypica - defluvii - flava - intermedia - palleronii - pseudoflava - taeniospiralis

Hydrogenophilus
hirschii

Hydrogenothermus
marinus

Hydrogenovibrio
marinus

Hylemonella
gracilis

Hymenobacter
aerophilus - chitinivorans - gelipurpurascens - norwichensis - ocellatus - roseosalivarius - sp.

Hyperthermus
butylicus

Hyphomicrobium
aestuarii - denitrificans - facile - methylovorum - sp. - sulfonivorans - zavarzinii

Hyphomonas
hirschiana - jannaschiana - neptunium - oceanitis - polymorpha