The Mole is a timid, nervous, and easily excitable character who has lived quietly in his underground home until the novel’s start, when spring fever lures him into an adventurous life more suitable to his sensibilities. His naiveté and curiosity provide opportunities for the other characters to explain simple facts about their world, and in this way serves an important narrative function. But the Mole is no bystander. He is eager to fully participate in the new world he explores, even if he falters or makes mistakes while doing so. He is also a fast learner, humble when corrected, and quick to help a friend, making him a foil for the Toad. They both tend to get easily worked up over a new idea, such as a boat or a motor car, but the Mole takes advice from those who are older or wiser than he is, while the Toad resents what he perceives as their interference.  

Despite being a small, underground dweller with little knowledge of life along the river or in the meadow and its hedges, the Mole is a kind, thoughtful, and generous friend. As he and the Water Rat explore the river, the two become close. Through the Water Rat, the Mole learns to appreciate the Otter and the Badger, although they carry a whiff of the danger that surrounds the creatures of the Wild Wood. The depth of the Mole’s feelings is best portrayed in Chapter V, “Dulce Domum,” in which the Mole is willing to deny his own powerful instinct to return home to accommodate his friend the Water Rat. The Mole’s home is clearly a cherished space, full of memorabilia that he treasures, but even when he is in his home and amongst his treasures, the Mole shows humility and gratitude, putting him thematically at the novel’s center.