Harry Haller The protagonist who also refers to himself as the Steppenwolf. He is suicidal because he cannot completely separate himself from bourgeois society. He discovers the Magic Theater and the "Treatise on the Steppenwolf" and begins a journey of self-discovery.
The Nephew The narrator in "The Preface." The nephew resides in the house where Steppenwolf is renting a room. Initially, the nephew despises Steppenwolf, but later they become friends. Steppenwolf leaves his personal manuscript behind and directs the nephew to do as he likes with it.
The Aunt Steppenwolf's landlady. She rents rooms to Steppenwolf and represents the epitome of bourgeois domesticity.
The Peddler The man carrying a sign for the Magic Theater. He gives Steppenwolf the pamphlet entitled, "Treatise on the Steppenwolf."
Hermine The woman Steppenwolf encounters at The Black Eagle. She prevents him from committing suicide the night of their first meeting. Later, she teaches him to dance, introduces him to Maria, and ultimately arranges his visit to the Magic Theater. Hermine informs Steppenwolf that they will be lovers in the future.
Maria Steppenwolf's lover. She dances with Steppenwolf after his first dance lesson with Hermine. Days later, she surprises him by waiting for him in his room. She teaches him about physical pleasure and sexual gratification. The affair lasts for the three weeks leading up to the Fancy Dress Ball.
Pablo A musician and friend to Hermine. He has access to mind-altering drugs. Although he is initially aloof to Steppenwolf, they become friends, and later it is revealed that he operates the Magic Theater.
Erica A friend to Steppenwolf. Her picture hangs in his room. They visit periodically but do not get along well.
The Professor An old acquaintance. He and Steppenwolf used to discuss Oriental mythology. A chance meeting prompts the professor to invite Steppenwolf to dinner.
Attorney-General Loering Victim to Steppenwolf and Gustav. The Attorney-General is an individual riding in one of the cars that is fired upon by Steppenwolf and Gustav during the Magic Theater sequence "JOLLY HUNTING. GREAT HUNT IN AUTOMOBILES." He debates the concept of duty with Gustav and ultimately convinces Gustav that he was only performing his duty when he sentenced individuals to death. Gustav decides not to kill him.
Gustav Steppenwolf's old friend. He is a theologian, but he puts his religious convictions aside to help Steppenwolf assassinate as many people in cars as they can during one sequence in the Magic Theater. Steppenwolf encounters Gustav when he enters the door entitled, "JOLLY HUNTING. GREAT HUNT IN AUTOMOBILES."
Goethe One of the Immortals. Steppenwolf encounters him during a dream sequence. Goethe informs Steppenwolf that he is taking life too seriously.
Mozart One of the Immortals. Steppenwolf encounters him after seeing the gallery entitled "HOW ONE KILLS FOR LOVE." Steppenwolf considers Mozart to be an infallible authority — not only one of the Immortals, but the purest and most respectable of them all. Mozart informs Steppenwolf that his serious nature and his failed attempt to separate himself from the bourgeoisie have led to his downfall.