Orphaned as an infant, Jane Eyre lives with at Gateshead with her aunt, Sarah Reed, as the novel opens. Jane is ten years old, an outsider in the Reed family. Her female cousins, Georgiana and Eliza, tolerate, but don't love her. Their brother, John, is more blatantly hostile to Jane, reminding her that she is a poor dependent of his mother who shouldn't even be associating with the children of a gentleman. One day he is angered to find Jane reading one of his books, so he takes the book away and throws it at her. Finding this treatment intolerable, Jane fights back. She is blamed for the conflagration and sent to the red-room, the place where her kind Uncle Reed died. In this frightening room, Jane thinks she sees her uncle's ghost and begs to be set free. Her Aunt Reed refuses, insisting Jane remain in her prison until she learns complete submissiveness. When the door to the red-room is locked once again, Jane passes out. She wakes back in her own room, with the kind physician, Mr. Lloyd, standing over her bed. He advises Aunt Reed to send Jane away to school, because she is obviously unhappy at Gateshead.

Jane is sent to Lowood School, a charity institution for orphan girls, run by Mr. Brocklehurst. A stingy and mean-hearted minister, Brocklehurst provides the girls with starvation levels of food, freezing rooms, and poorly made clothing and shoes. He justifies his poor treatment of them by saying that they need to learn humility and by comparing them to the Christian martyrs, who also endured great hardships. Despite the difficult conditions at Lowood, Jane prefers school to life with the Reeds. Here she makes two new friends: Miss Temple and Helen Burns. From Miss Temple, Jane learns proper ladylike behavior and compassion; from Helen she gains a more spiritual focus. The school's damp conditions, combined with the girls' near-starvation diet, produces a typhus epidemic, in which nearly half the students die, including Helen Burns, who dies in Jane's arms. Following this tragedy, Brocklehurst is deposed from his position as manager of Lowood, and conditions become more acceptable. Jane quickly becomes a star student, and after six years of hard work, an effective teacher. Following two years of teaching at Lowood, Jane is ready for new challenges. Miss Temple marries, and Lowood seems different without her. Jane places at advertisement for a governess position in the local newspaper. She receives only one reply, from a Mrs. Fairfax of Thornfield, near Millcote, who seeks a governess for a ten-year old girl. Jane accepts the job.

At Thornfield, a comfortable three-story country estate, Jane is warmly welcomed. She likes both her new pupil, Adèle Varens, and Mrs. Fairfax, the housekeeper at Thornfield, but is soon restless. One January afternoon, while walking to Millcote to mail a letter, Jane helps a horseman whose horse has slipped on a patch of ice and fallen. Returning to Thornfield, Jane discovers that this man is Edward Fairfax Rochester, the owner of Thornfield and her employer. He is a dark-haired, moody man in his late thirties. Although he is often taciturn, Jane grows fond of his mysterious, passionate nature. He tells Jane about Adèle's mother, Céline, a Parisian opera-singer who was once his mistress. Adèle, he claims, is not his daughter, but he rescued the poor girl after her mother abandoned her.

Jane also discovers that Thornfield harbors a secret. From time to time, she hears strange, maniacal laughter coming from the third story. Mrs. Fairfax claims this is just Grace Poole, an eccentric servant with a drinking problem. But Jane wonders if this is true. One night, Jane smells smoke in the hallway, and realizes it is coming from Rochester's room. Jane races down to his room, discovering his curtains and bed are on fire. Unable to wake Rochester, she douses both him and his bedding with cold water. He asks her not to tell anyone about this incident and blames the arson on Grace Poole. Why doesn't he press charges on Grace, or at least evict her from the house, Jane wonders.

Following this incident, Rochester leaves suddenly for a house party at a local estate. Jane is miserable during his absence and realizes she is falling in love with him. After a weeklong absence, he returns with a party of guests, including the beautiful Blanche Ingram. Jane jealously believes Rochester is pursing this accomplished, majestic, dark-haired beauty. An old friend of Rochester's, Richard Mason, joins the party one day. From him, Jane learns that Rochester once lived in Spanish Town, Jamaica. One night, Mason is mysteriously attacked, supposedly by the crazy Grace Poole.

Jane leaves Thornfield for a month to attend her aunt, who is on her deathbed following her son John's excessive debauchery and apparent suicide. Jane tries to create a reconciliation with her aunt, but the woman refuses all Jane's attempts at appeasement. Before dying, she gives Jane a letter from her uncle, John Eyre, who had hoped to adopt Jane and make her his heir. The letter was sent three years ago, but Aunt Reed had vindictively kept it from Jane. Sarah Reed dies, unloved by her daughters.

When Jane returns to Thornfield, the houseguests have left. Rochester tells Jane he will soon marry Blanche, so she and Adèle will need to leave Thornfield. In the middle of this charade, Jane reveals her love for him, and the two end up engaged. Jane is happy to be marrying the man she loves, but during the month before the wedding she is plagued by strange dreams of a destroyed Thornfield and a wailing infant. Two nights before the wedding, a frightening, dark-haired woman enters her room and rips her wedding veil in two. Although Jane is certain this woman didn't look like Grace Poole, Rochester assures her it must have been the bizarre servant. The morning of the wedding finally arrives. Jane and Rochester stand at the altar, taking their vows, when suddenly a strange man announces there's an impediment to the marriage: Rochester is already married to a woman named Bertha Antoinetta Mason. Rochester rushes the wedding party back to Thornfield, where they find his insane and repulsive wife locked in a room on the third story. Grace Poole is the woman's keeper, but Bertha was responsible for the strange laughter and violence at Thornfield. Rochester tries to convince Jane to become his mistress and move with him to a pleasure villa in the south of France.

Instead, Jane sneaks away in the middle of the night, with little money and no extra clothing. With twenty shillings, the only money she has, she catches a coach that takes her to faraway Whitcross. There, she spends three days roaming the woods, looking for work and, finally, begging for food. On the third night, she follows a light that leads her across the moors to Marsh End (also called Moor House), owned by the Rivers family. Hannah, the housekeeper, wants to send her away, but St. John Rivers, the clergyman who owns the house, offers her shelter. Jane soon becomes close friends with St. John's sisters, Diana and Mary, and he offers Jane a humble job as the schoolmistress for the poor girls in his parish at Morton. Because their father lost most of his money before he died, Diana and Mary have been forced to earn a living by working as governesses.

One day, St. John learns that, unbeknownst to her, Jane has inherited 20,000 pounds from her uncle, John Eyre. Furthermore, she discovers that St. John's real name is St. John Eyre Rivers, so he, his sisters, and Jane are cousins. The Rivers were cut out of John Eyre's will because of an argument between John and their father. Thrilled to discover that she has a family, Jane insists on splitting the inheritance four ways, and then remodels Moor House for her cousins, who will no longer need to work as governesses. Not content with his life as a smalltime clergyman, St. John plans to become a missionary in India. He tries to convince Jane to accompany him, as his wife. Realizing that St. John doesn't love her but just wants to use her to accomplish his goals, Jane refuses his request, but suggests a compromise by agreeing to follow him to India as a comrade, but not as a wife. St. John tries to coerce her into the marriage, and has almost succeeded, when, one night Jane suddenly hears Rochester's disembodied voice calling out to her.

Jane immediately leaves Moor House to search for her true love, Rochester. Arriving at Millcote, she discovers Thornfield a burned wreck, just as predicted in her dreams. From a local innkeeper, she learns that Bertha Mason burned the house down one night and that Rochester lost an eye and a hand while trying to save her and the servants. He now lives in seclusion at Ferndean.

Jane immediately drives to Ferndean. There she discovers a powerless, unhappy Rochester. Jane carries a tray to him and reveals her identity. The two lovers are joyfully reunited and soon marry. Ten years later, Jane writes this narrative. Her married life is still blissful; Adèle has grown to be a helpful companion for Jane; Diana and Mary Rivers are happily married; St. John still works as a missionary, but is nearing death; and Rochester has regained partial vision, enough to see their first-born son.