One spring morning, Fern Arable sees her father going out to the hoghouse with an ax. Her mother tells her that some pigs had been born the night before, but one of them was a runt, so her father was going to do away with it.

Enraged by what she saw as an injustice, Fern runs to her father and he agrees not to kill the baby pig - as long as she raises it herself. The pig is named Wilbur, and Fern cares for him happily.

When Wilber turns five weeks old he is sold to Fern's uncle, Homer Zuckerman. Despite no longer being his caretaker, Fern visits him almost every day.

In his new home Wilber makes new aquaintances among the animals, but soon grows lonely. Then he meets Charlotte, a spider who lives in the doorway over his pen. Charlotte says she will be his friend and Wilbur is excited, although he is alarmed by Charlotte's eating habits. Charlotte's kindness and good nature win Wilbur over, and they become good friends.

Wilbur's new happiness is short-lived, however, when he learns that Mr. Zuckerman is planning to kill him at Christmastime and turn him into smoked bacon and ham. Wilbur goes hysterical at the news, but Charlotte hatches a clever plan that will save Wilbur's life and take them all the way to the county fair.

The story of Charlotte's effort to save Wilbur is a lesson is selfless love that demostrates the beauty of true friendship and sacrifice.