- Kakamega Greenbul
- Kalahari Scrub Robin
- Kalij Pheasant
- Kalkadoon Grasswren
- Kandt's Waxbill
- Karoo Chat
- Karoo Eremomela
- Karoo Korhaan
- Karoo Lark
- Karoo Long-billed Lark
- Karoo Prinia
- Karoo Scrub Robin
- Karoo Thrush
- Karthala White-eye
- Kashmir Flycatcher
- Kea
- Keel-billed Motmot
- Keel-billed Toucan
- Kelp Goose
- Kelp Gull
- Kenrick's Starling
- Kentish Plover
- Kentucky Warbler
- Kenya Sparrow
- Kikuyu Mountain Greenbul
- Kikuyu White-eye
- Killdeer
- Kilombero Cisticola
- Kilombero Weaver
- King Bird-of-paradise
- King Penguin
- King Vulture
- Kirk's White-eye
- Kittlitz's Plover
- Klaas's Cuckoo
- Kloss's Leaf Warbler
- Knob-billed Duck
- Knobbed Hornbill
- Knysna Turaco
- Kolombangara Monarch
- Kori Bustard
- Kozlov's Accentor
- Kretschmer's Longbill
- Kurrichane Thrush