- Millie Dillmount: a young woman who leaves her hometown in the Midwest to pursue a new life in New York City.
- Trevor Graydon: a wealthy and charming young man from a prominent New York family.
- Muzzy Van Hossmere: a dim-witted and socialite friend of Millie's who is also from a wealthy family.
- Mrs. Meers: the owner of a boarding house where Millie and Muzzy stay.
- Ching Ho: the adopted daughter of Mrs. Meers who is forced to work as a servant in the boarding house.
- Dorothy Brown: a young woman from Kansas who is also staying at the boarding house and is looking for a job.
- Jimmy Smith: a bellhop at the hotel where Millie and Trevor are staying.
- Mr. Graydon: Trevor's father and a wealthy businessman.
- Mrs. Graydon: Trevor's mother and a socialite.