The Walrus is a large, talking sea mammal who strolls along a sandy beach with his human companion. He possesses a highly talkative and charismatic nature, quickly striking up conversations with those he meets. He uses polite invitations and displays of emotion, such as holding a pocket-handkerchief to his eyes, to mask his true intentions and assert authority over smaller creatures.

The Carpenter is a human tradesman who accompanies the Walrus on a walk along the shore. Unlike his talkative companion, he is blunt, direct, and focused heavily on practical matters like food preparation. He participates fully in luring the sea creatures away from their beds but refuses to feign sympathy or manners while doing so.

Alice is a young girl traveling through a fantasy world where logic operates in reverse. As the audience for the poem, she actively questions the actions and morality of the characters she hears about. She tries to determine whether manipulative charm or blunt cruelty is worse, reflecting an active desire to understand adult behavior.

The Young Oysters are a large group of naive sea creatures living in an ocean bed. They exhibit human characteristics, wearing brushed coats and clean shoes even though they lack feet. They possess a childlike trust in authority figures and eagerly leave the safety of the water when promised a pleasant walk and engaging conversation.

The Eldest Oyster is a mature and experienced resident of the underwater oyster-bed. When approached by strangers offering a pleasant walk, he remains completely silent. He communicates his refusal simply by winking his eye and shaking his head, utilizing his age and life experience to avoid unfamiliar situations.

The Sun is an anthropomorphized male celestial body who shines with all his might over the ocean. His appearance directly contradicts the natural order, as he blazes brightly when the day is supposed to be done. His overbearing presence sets a strange, inverted tone for the events on the beach below.

The Moon is an anthropomorphized female celestial body presiding over the night sky. She acts sulky and frustrated because she feels her natural evening domain is being invaded. She strictly prefers routine and views the sun's nighttime appearance as an intentional attempt to spoil her hours of rule.

Tweedledum is one half of a pair of identical twins living in the looking-glass world. Derived from a traditional nursery rhyme, he acts as a storyteller to the young visitor. He uses verses filled with backward logic and talking animals to entertain and subtly challenge his guest.

Tweedledee is the twin brother of Tweedledum and a resident of the looking-glass world. Together with his brother, he recites the verses about the beach and the sea creatures to Alice. He presents her with a narrative full of wordplay and hidden cautionary lessons about blind obedience.