Dumbo is an elephant of Auradon. He now lives in a circus.
In his debut, after being delivered by Mr. Stork, he is named "Jumbo, Jr." by his mother, Mrs. Jumbo and all the other female elephants remark on his cute looks. Dumbo then sneezes after the Elephant Matriarch tickles him on his trunk and reveals that his ears are much larger than average. As soon as his big ears are revealed, he is teased with the other female elephants, who call him "Dumbo". After Dumbo's mother closes the door to their stalls, she and Dumbo rest peacefully. Dumbo later takes part in setting up the circus tent with his mother and the other elephants and circus animals at night as they arrive to their destination.
The next day, Dumbo takes part in the opening parade for the circus with his mother and the other elephants, but trips on his ears and falls in a mud puddle, thus, causing everyone to laugh at him. A few moments later, Dumbo is given a bath by his mother and they spent time playing with one another. Once people come into the circus for a tour to see the circus animals, Dumbo gets laughed at by some boy bullies and his ears are pulled by a boy who wanted to tease him, thus, considered a laughingstock to them. When his mother tries to protect him, she is believed to be mad, and is captured and imprisoned by the Ringmaster and his guards. Dumbo is left by himself feeling sad, while the other elephants laugh at him and regard him a disgrace. When Dumbo tries to have a hay meal with the other female elephants, they give him the cold shoulder and he walks away without a friend in the world until he meets his soon-to-be best friend, Timothy, whom he was afraid of at first when Timothy scared all the elephants for picking on Dumbo, but then, Dumbo and Timothy become friends when Timothy offers to help him get his mother out of the clink.
Timothy, having overheard the teasing Dumbo endures earlier, decides to help Dumbo become a circus star. The first attempt ends in failure, as Dumbo once again trips on his ears while attempting to jump to the top of a "Pyramid of Pachyderms" as the climax resulting collapsing the big top and all of the elephants injured, he then emerges his trunk through a hole on the big top swinging his flag, but it break in half due to the collapse of the big top leaving him swinging what's left of his flag. The failure results in the circus making Dumbo into a clown, which depresses Dumbo and makes him a real laughingstock to the circus, the people, the clowns, and the other elephants. To cheer him up, Timothy takes Dumbo to visit his mother, but the visit ends too soon.
Later, Dumbo and Timothy accidentally become drunk when they drink water that has been accidentally mixed with alcohol due to the clowns' clumsiness. Both begin hallucinating; seeing Pink Elephants. When they awaken, they somehow end up in a tree after meeting some crows, who are amused by an elephant being in a tree and tell them about their situation. After getting back down to the ground while falling from the tree, Timothy wonders if Dumbo either jumped or climbed up to the tree until he finally comes to believe that Dumbo flew (due to one of the crows' ironic suggestion), thus, amusing the crows and making them sing "When I See an Elephant Fly". But after Timothy tells them Dumbo's sad story, they feel sad and bad about their earlier action and decide to help Dumbo use his ears as wings to fly and to use the "magic feather" as a token to encourage and increase Dumbo's confidence. Dumbo is finally seen flying in the air, much to Timothy and the crows' amazement and delight.
At the circus' next stop, during the act, Dumbo is able to fly without the help of the magic feather after accidentally losing it and after Timothy begs him to open his ears, therefore, impressing the crowd and allowing Dumbo to get some payback on those who teased him by taking off a clown's mask resembling Dumbo's mother, throwing it on the Ringmaster's buttocks who ends up getting his head dunked into a bucket of water, causing the clowns to accidentally burn themselves on their buttocks, then he decides to vacuum up some peanuts with his proboscis from a peanut seller's stand, and spray those peanuts on his rude aunts and Mrs. Jumbo's "sisters". Dumbo becomes the greatest star in America with Timothy as his manager.
At the end of the film, it is shown that Dumbo's mother has been released and the two share their own private coach, they then wave goodbye to the crows who are standing in an electric pole.
- He is the fifth character not to talk in their debut, the first being Dopey, the second Gideon, the third Yen Sid, the fourth Chernabog, and the sixth Tinker Bell.
- He is the first Disney Protagonist that is an animal.