- MacGregor's Honeyeater
- Magnificent Bird-of-paradise
- Magpie-lark
- Magpie Goose
- Maguari Stork
- Makira Honeyeater
- Makira White-eye
- Malabar Trogon
- Malayan Crested Fireback
- Malayan Peacock-Pheasant
- Malaysian Hawk-Cuckoo
- Malleefowl
- Mandarin Duck
- Maned Duck
- Mangrove Honeyeater
- Manx Shearwater
- Many-banded Aracari
- Marbled Duck
- Marbled Frogmouth
- Marbled Honeyeater
- Marbled Wood Quail
- Marmora's Warbler
- Maroon-backed Accentor
- Maroon Oriole
- Marsh Babbler
- Marsh Sandpiper
- Marsh Warbler
- Masked Booby
- Masked Bowerbird
- Masked Lapwing
- Meadow Pipit
- Melodious Warbler
- Merlin
- Metallic Pigeon
- Metallic Starling
- Mexican Woodnymph
- Mid-mountain Berrypecker
- Middle Spotted Woodpecker
- Mindanao Bleeding-heart
- Mistle Thrush
- Modest Tiger Parrot
- Mongolian Finch
- Mongolian Ground Jay
- Montezuma Quail
- Morepork
- Mottled Flowerpecker
- Mottled Wood Owl
- Mountain Quail
- Mountain Trogon
- Moustached Laughingthrush
- Moustached Treeswift
- Moustached Warbler
- Mulga Parrot
- Musk Duck
- Mute Swan