Fourteen-year-old Travis Coates is left in charge of his family’s ranch while his Papa sets off on a long cattle drive from their Texas Hill Country home to Abilene, Kansas. Papa entreats Travis to act like “the man of the family” in his absence, and Travis promises to take good care of his Mama and his little brother, Arliss. He immediately sets to work on the many tasks that need to be done around the ranch. The next morning, when Travis goes out to fetch some meat from the storehouse, he finds a big yellow dog sleeping on the ground—the dog has eaten all of the meat. Travis yells at the dog and chases it away, but Little Arliss runs outside and defends the dog. Mama lets Little Arliss keep the dog—much to Travis’s chagrin—and they nickname him Old Yeller for his humanlike bark.
Over the next several weeks, Travis is desperate to prove his manliness and responsibility—but he underestimates how dangerous the natural world can be, such as when a pair of fighting bulls nearly destroy the Coateses’ cabin. When Old Yeller rescues Little Arliss from an angry bear one afternoon, Travis’s attitude toward the dog changes: he finds himself doting on Old Yeller and appreciating his company.
One afternoon, a neighbor, Bud Searcy, drops by with his granddaughter Lisbeth. The two of them bring their female hound, and Old Yeller mates with her. Bud informs the Coates family that some kind of “strange varmint” has been ransacking vegetable patches and storehouses around the countryside. Lisbeth also takes Travis aside and tells him that she saw Old Yeller stealing from her family’s stores. After this, Travis becomes even more protective of Old Yeller and enlists the dog’s help in all of his daily tasks around the homestead.
One day, a young cowboy named Burn Sanderson arrives and claims that he’s Old Yeller’s true owner—Old Yeller had accompanied him on a months-long cattle drive and recently ran away. But when Bud sees how much the boys love the dog, he lets them keep him. After having dinner with the family, Burn takes Travis aside and tells him that a plague of hydrophobia (rabies) has begun to ravage the surrounding area. Burn urges Travis to be cautious in the wilderness and to protect his family by shooting any animal that behaves strangely or aggressively. Hydrophobia, Burn warns, is highly contagious—and even humans can get the terrible disease. Travis is terrified, but the next morning he brings Old Yeller with him while he does the difficult work of tagging the Coateses’ hogs.
A few days later, Bud comes by to report that he saw a pack of young hogs that Travis missed out by some bat caves a little ways away. Travis excitedly heads out to the caves with Old Yeller in tow. He attempts to tag the hogs from the shelter of a sandbank—but the bank breaks, and the hogs severely injure Travis and Old Yeller with their tusks.
Over the next several weeks, Travis and Old Yeller slowly recover from their serious wounds. Bud Searcy and Lisbeth come around again: Lisbeth has brought a puppy (the offspring of her hound and Old Yeller), and she offers it to Travis as a gift. Travis tells her that he already has a dog, so Lisbeth gives the puppy to Little Arliss instead. Then, Bud announces that he’s leaving Lisbeth with the Coateses to help out around the house while Travis and Old Yeller recover. Travis is embarrassed to cede his duties to a girl—but Mama is grateful for the help, and Lisbeth is good company.
One evening, when Travis’s leg is nearly healed, he hears a strange noise outside: the family’s milk heifer, Spot, is moaning and walking in circles. Then, Spot charges at Mama, frightening her. Travis wonders aloud if cows can get hydrophobia too. Spot’s condition worsens over the next several days, and an aggressive roan bull also staggers onto their property. Travis kills the bull, and they burn the body. Mama tells Travis that they have to kill and burn Spot as well. Travis is sad, but he steels his nerves and shoots Spot.
Mama and Lisbeth go out to gather more firewood for Spot’s pyre. They take Old Yeller with them for protection—Travis is still too weak to walk long distances or haul anything home. When Mama and Lisbeth don’t return by dark, Travis gets worried. Soon, he hears screams and growls. Mama calls for him to grab his gun, and Travis runs outside to see Old Yeller tussling with a rabid wolf in the front yard. When the wolf grabs Old Yeller by the throat, Travis shoots and kills the wolf. Old Yeller happily and gratefully licks Travis’s hands, but Mama starts to cry. She tells Travis that the wolf bit Old Yeller, so he must be put down before hydrophobia gets to him. Travis feels numb and dead inside as he shoots and kills Old Yeller.
After Old Yeller’s death, Travis spends many days feeling heartbroken and empty; nothing and no one can comfort him. When Papa finally returns home, he tries to tell Travis how proud he is of him for taking care of so many hard things while he was away. He urges Travis to forget about what happened to Old Yeller and keep being a strong man. Travis is devastated—he has no idea how he’s supposed to forget his best friend.
A week later, as Travis hears a ruckus in the kitchen: Arliss’s pup (the one fathered by Old Yeller) runs out of the house with a piece of cornbread in his mouth. Travis laughs at the dog’s antics, which remind him of Old Yeller. That evening, after a long walk through the woods, Travis returns home to find Little Arliss and the pup playing happily. Travis begins to laugh and cry simultaneously, experiencing a huge emotional release. He decides that it’s time to take them both out on a squirrel hunt the next day—it’s time for the pup, like his father before him, to start earning his keep.
