Charlie Gordon
The protagonist of the story who authors the writings or "progress reports" throughout the book. Charlie is a 32-year-old mentally disabled man who resides in New York City. He works at a small shop called Donner's Bakery where he is the Janitor and Delivery Boy. He always has an eager and happy attitude and when he enrolls in a literature class for mentally disabled adults he excels (at least in comparison to his peers). He undergoes a surgery to become more intelligent and soon after gains a massive amount of knowledge becoming a genius in a matter of days. However, his maturity and intelligence are not parallel and this becomes a large internal conflict for him throughout the story.
Algernon
The white laboratory mouse who was the original test of the experiment that was later performed on Charlie. This mouse becomes three times as smart as all other mice and is able to solve complex puzzles.
Alice Kinnian
Charlie's teacher in his literature class for mentally disabled adults who is impressed by his hard work and motivation. She recommends him for the procedure originally, and oversees that he is doing well in the hands of the scientists throughout the book. She is the only woman who Charlie loves while he is intelligent, and it is only for a brief period.
Professor Harold Nemur
The scientist who runs the experiment that boosts Charlie's intelligence. He does not care for Charlie and merely sees him as a laboratory animal like Algernon. He has little to no concern for the well-being of his patient.
Dr. Strauss
The neurologist and psychiatrist who performs the surgery on Charlie. He works with Professor Nemur but is much more concerned about Charlie's health and wellness, and conducts therapy sessions with him to ensure he is in good condition.
Burt Selden
A graduate student who assists Nemur and Strauss in their experimentation. He is always very kind to Charlie.
Fay Lillman
Charlies neighbor and a fun-loving, free-spirited, sexually-active individual who has sexual relations with him at one point, knowing nothing of his background.
Rose Gordon
Charlie's abusive mother who did not accept the fact that her son was disabled. When she had a daughter after him, Norma, she focused all her energy on her instead. At times when Charlie was sexually confused, Rose punished him even though he knew no better.
Matt Gordon
Charlie's dad who works at a barbershop. Oftentimes he tries to save his son from Rose's abuse but fails and gives in to her bullying.
Norma Gordon
Charlie's sister who is a caretaker for her unstable mother. When she was young, she disliked Charlie because she believed he received "special treatment" and treated him poorly. She is regretful, however, when she sees him all grown up.
Uncle Herman
Charlie's uncle who takes him in after being sent away from his own house. Herman treats Charlie respectfully and ensures that he has a lifetime job at the bakery before he passes away.
Mr. Donner
Owner of Donner's Bakery where Charlie works. Donner is an old friend of Uncle Herman and promises to look after Charlie when Herman passes. He gives Charlie a lifetime job so he won't have to go into a home and treats him as family.
Frank Reilly and Joe Carp
Employees at the bakery where Charlie works. They often pick on him and play jokes on him that Charlie does not understand. However, they defend him when others mistreat him.
Gimpy
Employee at the bakery where Charlie works who steals from his boss. He has a similar relationship to Charlie as Frank and Joe.
Fanny Birden
Employee at the bakery who is the only one consistently nice to Charlie. She gets suspicious when he becomes intelligent that he struck a deal with the devil.
Dr. Guarino
A quack doctor who Charlie is taken to be seen by his mother. Gaurino uses fake methods to improve Charlie's intelligence, and swindles money from the Gordons.
Hilda
The nurse on duty when Charlie is recovering from his surgery. She believes he is defying the will of God.
Minnie
A mouse Fay purchases to befriend Algernon.
Meyer Klaus
A new employee at the bakery when Charlie resumes his job after losing his intelligence.
