The hero and protagonist of the novel. Myshkin is a descendant of an old noble line and a distant relative of Madame Yepanchin. He is a fair-haired, blue-eyed epileptic in his late twenties. He comes to Russia after an absence of four years spent in a sanitarium in Switzerland. Myshkin is innocent, naïve, impractical, compassionate, and immensely kind, which leads most characters in the novel to consider him an "idiot."
An immensely beautiful femme-fatale in her mid-twenties whom many of the characters call "mad." Nastassya Filippovna was once a ward of Totsky. Later, however, he seduced her and made her his mistress when she was a young woman. She blames herself for her dishonor and, although she loves Prince Myshkin, she considers herself unworthy of marrying him. Nastassya runs to Rogozhin, who later stabs her to death.
A dark-haired, dark-eyed twenty-seven year-old who is descended from a long line of merchants. Rogozhin is madly and passionately in love with Nastassya Filippovna. After receiving a large inheritance, he attempts to woo her by bringing her 100,000 rubles. She runs between him and Prince Myshkin until the end, when Rogozhin kills her.
A beautiful twenty-year-old beautiful and the youngest daughter of General Yepanchin and Lizaveta Prokofyevna. Aglaya is haughty and childlike in her caprices, but also very romantic and idealistic. She falls in love with Prince Myshkin, but is unable to accept his compassionate love for Nastassya Filippovna. Aglaya ends up running away with a man claiming to be a Polish count, who later abandons her.
A thin, fair-haired, good-looking young man of twenty-eight. Ganya is highly vain and ambitious. Although the epitome of mediocrity, he strives for originality. He is in love with Aglaya, but is willing to marry Nastassya Filippovna—whom he despises—for 75,000 rubles.
A fifty-six year-old general. Yepanchin is a wealthy and respected member of St. Petersburg society. At the beginning of the novel he lusts after Nastassya Filippovna.
A distant relative of Prince Myshkin and the wife of General Yepanchin. In her willfulness and eccentricity, Lizaveta is very similar to Aglaya. Her greatest anxiety in life is finding suitable husbands for her three daughters.
The oldest daughter of the Yepanchins, who is twenty-five and unmarried. Although Alexandra's parents worry about her marriage, she feels very calm. Highly educated and well read, she has a talent for music.
The middle daughter of the Yepanchins, who is twenty-three. Adelaida, like her older sister, is very cultivated and expresses a talent for painting. She is engaged to Prince S.
A seventeen year-old consumptive. Hippolite is well aware of his approaching death and feels like an outcast of nature. He tries to reassert himself by espousing his own views on life and morality in his "Essential Statement" and then by his suicide attempt, which proves unsuccessful. In love with Aglaya, Hippolite is a friend of Kolya and the son of Madame Terentyev, the mistress of General Ivolgin.
A rich aristocrat in his middle fifties, he tries to arrange the marriage between Nastassya Filippovna and Ganya to get her off his hands. Several years before the action of the novel takes place, he makes her his mistress for several years.
A young and dashing suitor to Aglaya Yepanchin. Radomsky retires from the military just before he takes part in the novel's action. A man of reason, he frequently visits Myshkin in the Swiss sanitarium at the end of the novel.
The good-looking and intelligent fiancé of Adelaida Yepanchin, who later on becomes her husband. Prince S. is hardworking, knowledgeable, and very rich.
A rogue, drunkard, liar, and recently widowed father of a large family. At the beginning of the novel, Lebedev is part of Rogozhin's gang. He later rents out several rooms in his summer cottage in Pavlovsk to Prince Myshkin.
An ordinary man just under thirty who manages to collect a large fortune by being a usurer (lending money for interest). Ptitsyn is suitor and later husband to Varya Ivolgin.
Ganya's father, an ex-general. General Ivolgin has lost his circle of friends in high society due to constant drinking and lying.
General Ivolgin's wife. Nina Alexandrovna, a dignified woman of about fifty, is the mother of Varya, Ganya, and Kolya Ivolgin. Despite her husband's lying and keeping of a mistress, she pities him and even helps Hippolite.
Ganya's dignified twenty-three-year-old sister. Varya is among the characters whom the narrator considers ordinary people. She tries to help her brother's chances with Aglaya by befriending the Yepanchin girls, but to no avail.
Ganya's teenage brother. Kolya is a simple and good-natured boy who becomes friends with Prince Myshkin, whom he respects greatly. Kolya is also friends with Hippolite, whom he visits throughout his illness until Hippolite's death from consumption.
An ugly and insolent lodger in the Ivolgin apartment at the beginning of the novel. Ferdyshchenko strives to be original, yet most people regard him contemptuously as a drunkard and an amoral rogue.
A young man who fraudulently claims to be the son of Pavlishchev, Myshkin's late benefactor. Burdovsky attempts to use the false claim to gain access to a portion of the prince's inheritance.