When an impulsive boy named Kenai is magically transformed into a bear, he must literally walk in another's footsteps until he learns some valuable life lessons. His courageous and often zany journey introduces him to a forest full of wildlife, including the lovable bear cub Koda, hilarious moose Rutt and Tuke, woolly mammoths, rambunctious rams and more!
Kenai, like a lot of young boys, have the eagerness to be recognized by others as a man. He has two older brothers: Sitka and Denahi. This is a big day for Kenai, as it is Kenai's manhood ceremony and he is getting a totem from the shaman woman of the tribe, Tanana.
Kenai fails to tie the brothers' daily catch on the tree. After the ceremony the basket and the fish gets taken by bears. Angered and raged, Kenai sets off to get the basket but only finds the broken pieces.
Kenai sees the bear, and starts throwing rocks at it. The bear is angered and charges at Kenai, causing him to fall off a cliff. His two brothers see his fall, and they come for rescue. Ultimately, Sitka gives his life to save his brothers.
So that very same day a memorial ceremony is held. Kenai blames the bear and sets off to kill it. Before he leaves he throws his totem -- a bear -- into the ashes. Kenai finds the bear after days of searching, and kills the bear. The spirits get involved as bear is the animal of Kenai's totem. Sitka, now a spirit, changes Kenai into a bear so that he can learn some lessons before regaining his human form.
Denahi does not see the transformation, but sees the remains of Kenai's clothing. Angered that the bear now killed both of his brother, he sets off to kill the bear.
Now that Kenai is a bear, he meets Tanana who explains to him what have happened and that now he must go to "where the lights touch the earch" to regain his human form. Not knowing how to get there, Kenai meets the two moose, Rutt and Tuke who just think Kenai is crazy. What's worse it that Kenai is now hung upside-down a tree! And Koda comes for the rescure -- and stories. Now Kenai must travel to "the salmon run" with Koda because Koda knows the way to the mountain!
Kenai arrives at the Salmon Run with Koda, meets Tug and other bears, and enjoys his stay at the Salmon Run with all his bear friends. Later on in the evening when all the bears gather and share their stories, Kenai shows his love and care for Koda, his new bear brother. However, as Koda relays his story, Kenai is shocked. Instead hearing a story of a man fighting against a monstrous bear, Koda brought a whole new view of the story -- a mom fighting against three hunters, trying to protect her cub, Koda. Kenai feels the guilt for his newfound brother and left the story circle.
The next morning Kenai confesses his tragic error and tells Koda the truth about his mother. Koda, sad and hurt, runs away and Kenai heads to the mountain, looking for a way to resolve things. The two moose, Rutt and Tuke, argues with each other and unintentionally gives Koda an explanation of what brothers are for, and Koda heads for the mountains after Kenai.
Denahi at this time catches up with Kenai and the two fight. When it seems Kenai is going to meet his end on Denahi's dagger, Koda enters the scene, knocking Denahi off and Denahi turns and runs for his lasts weapon -- a spear -- and Kenai runs after to protect Koda. Denahi turns and points the spear towards the charging Kenai, much like how Kenai killed Koda's mother.At this very moment the spirits intervened and Sitka changes Kenai back into a man. After a brief discussion, Kenai decides to stay as a bear to look after Koda. While Kenai is changing back into a bear, Koda's mom appears and says goodbye to her cub. At last, Kenai earns his place to put his paw print next to those handprints of his ancestors on the wall.
Story to be continued in Brother Bear 2...