The characters in "The Importance of Being Earnest" by Oscar Wilde are:

1. Jack Worthing: The protagonist of the play, who is also known as Ernest. He is a wealthy young man who lives in the country and pretends to have a younger brother named Ernest in order to escape his dull life and visit the city.
2. Algernon Moncrieff: Jack's friend and a dandy who lives in the city. He is also known as Ernest when he visits the country to woo Jack's ward, Cecily.
3. Gwendolen Fairfax: Algernon's cousin and Jack's love interest. She is a fashionable and sophisticated young woman who is obsessed with the name Ernest.
4. Lady Bracknell: Gwendolen's mother and a formidable society matron. She is obsessed with social status and is determined to find a suitable husband for her daughter.
5. Cecily Cardew: Jack's ward and the object of Algernon's affection. She is a romantic and imaginative young woman who is also obsessed with the name Ernest.
6. Miss Prism: Cecily's governess who is also a writer. She is responsible for a secret from Jack's past that is revealed later in the play.
7. Rev. Canon Chasuble: The local vicar who is also a scholar. He is romantically interested in Miss Prism.
8. Lane: Algernon's butler who is also a confidant and accomplice in his schemes.
9. Merriman: Jack's butler who is also a messenger and a source of information.