- Hackberry Emperor
- Hackberry Nipplegall Psyllid
- Hackberry Petiole Gall Psyllid
- Hairy Carpenter Ant
- Hairy Woodpecker
- Hairy-footed Flower Bee
- Half-black Bumble Bee
- Half-edged Wall Jumping Spider
- Half-wing Moth
- Halloween Pennant
- Harbor Seal
- Hardhead
- Harlequin Bug
- Harlequin Duck
- Harris's Hawk
- Harris's Sparrow
- Hawaiian Beet Webworm Moth
- Hawfinch
- Hawthorn Shield Bug
- Heart and Dart
- Heath Fritillary
- Heather crab spider
- Hebrew Character
- Hebrew Moth
- Heermann's Gull
- Helmeted Guineafowl
- Hemlock Looper Moth
- Hemlock Woolly Adelgid
- Hen Harrier
- Hepatic Tanager
- Herald Moth
- Hermit Thrush
- Hickory Tussock Moth
- High Brown Fritillary
- Hoary Comma
- Hoary Marmot
- Hobomok Skipper
- Hollow-spotted Blepharomastix Moth
- Holly Blue
- Hooded Crow
- Hooded Merganser
- Hooded Oriole
- Hooded Siskin
- Hooded Warbler
- Hook-streaked Grass-veneer
- Hopkins' Rose Nudibranch
- Horace's Duskywing
- Horned Grebe
- Horned Lark
- Horned Nudibranch
- Horned Passalus Beetle
- Horned Spanworm Moth
- Hornet Mimic Hover Fly
- Horse-chestnut Leafminer
- House Centipede
- House Crow
- House Finch
- House Mouse
- House Sparrow
- Hudsonian Whimbrel
- Hummingbird Clearwing
- Hump-backed Beewolf
- Humpback Whale
- Hunt's Bumble Bee
- Hunter's Little Paper Wasp
- Huron Skipper
- Hutton's Vireo