"The Boys" 4. sezon oyuncuları şunlardır: Karl Urban - William "Billy" Butcher; Jack Quaid - Hugh "Hughie" Campbell Jr; Antony Starr - John, Homelander; Erin Moriarty - Annie January, Starlight; Jessie T. Usher - Reggie Franklin, A-Train; Laz Alonso - Marvin T. "Mother's" Milk; Chace Crawford - Kevin Moskowitz, The Deep; Tomer Capone - Serge, Frenchie; Karen Fukuhara - Kimiko Miyashiro; Nathan Mitchell - Black Noir II; Colby Minifie - Ashley Barrett; Claudia Doumit - Victoria "Vic" Neuman; Cameron Crovetti - Ryan; Susan Heyward - Sister Sage; Valorie Curry - Firecracker; Jeffrey Dean Morgan - Joe Kessler.