Read below for information on 10 different animals that start with the letter O, from ocelot to oyster. The most popular animal that starts with the letter O is the ocelot, a small cat also known as the painted leopard. The least popular O animal is the orangutan. Some can grow to be up to 200lbs, making them one of the largest primates in the world. Some fun facts about letter O name animals are:
- Opossums are believed to be immune to some snake venom
- With males growing over 9 feet tall, ostriches are the world’s largest bird
- Otters hold hands while sleeping to avoid drifting apart while in flowing water
Popular Animals starting with O

Ocelot
Also known as the Painted Leopard!

Old English Sheepdog
Intelligent, sociable and playful!
Animals that Start with O
We’ve broken down all of our animals into family groups. You’ll find mammals, birds, fish, reptiles, amphibians, insects, and other invertebrates below!
Jump to a specific list:
- Mammals that Start with O
- Birds that Start with O
- Fish that Start with O
- Reptiles that Start with O
- Amphibians that Start with O
- Insects that Start with O
- Other Invertebrates that Start with O
Mammals that Start with O

Ocelot
Also known as the Painted Leopard!

Okapi
Eats more than 100 different types of plant!

Old English Sheepdog
Intelligent, sociable and playful!

Opossum
Thought to be immune to certain snake venom!

Orang-utan
Shares 97% of its DNA with humans!

Otter
There are 13 different species worldwide
View all mammals.
Birds that Start with O

Ostrich
The largest bird in the world!
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Fish that Start with O
No animals found.
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Reptiles that Start with O
No animals found.
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Amphibians that Start with O

Olm
Inhabits dark underwater caves
View all amphibians.
Insects that Start with O
No animals found.
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Other Invertebrates that Start with O
View all invertebrates.
Alphabetical List of Animals That Start with O
Newest Animals that Start with the Letter O
The most recently added Animals that start with the letter O.

Opossum
Thought to be immune to certain snake venom!

Octopus
There are around 300 different species!

Otter
There are 13 different species worldwide

Animal by Letter Lists
- Animals that Start with A
- Animals that Start with B
- Animals that Start with C
- Animals that Start with D
- Animals that Start with E
- Animals that Start with F
- Animals that Start with G
- Animals that Start with H
- Animals that Start with I
- Animals that Start with J
- Animals that Start with K
- Animals that Start with L
- Animals that Start with M
- Animals that Start with N
- Animals that Start with O
- Animals that Start with P
- Animals that Start with Q
- Animals that Start with R
- Animals that Start with S
- Animals that Start with T
- Animals that Start with U
- Animals that Start with V
- Animals that Start with W
- Animals that Start with X
- Animals that Start with Y
- Animals that Start with Z