Chadwick Boseman
as James Brown

Nelsan Ellis
as Bobby Byrd

Dan Aykroyd
as Ben Bart

Viola Davis
as Susie Brown

Lennie James
as Joe Brown

Fred Melamed
as Syd Nathan

Jill Scott
as DeeDee Brown

Octavia Spencer
as Aunt Honey

Nick Eversman
as Mick Jagger

Tika Sumpter
as Yvonne Fair

James DuMont
as Corporal Dooley

Billy Slaughter
as Pool Cleaner

Ritchie Montgomery
as Warden

Craig Robinson
as Maceo Parker

Brandon Mychal Smith
as Little Richard

Aloe Blacc
as Nafloyd Scott

Josh Hopkins
as Ralph Bass

Aunjanue Ellis-Taylor
as Vicki Anderson

Tariq Trotter
as Pee Wee Ellis

Keith D. Robinson
as Baby Roy

Stacey Scowley
as Penelope White

Liz Mikel
as Gertrude Sanders

Julius Tennon
as Grandpa Byrd

Allison Janney
as Kathy

John Benjamin Hickey
as Richard

J.D. Evermore
as Seminar Presenter

Carol Lee
as Mavis

Cleta Elaine Ellington
as Shirley Buell

Jim Gleason
as Insurance Salesman

Ahna O'Reilly
as Reporter

Antonius Charles
as Black Infantryman

Donald Watkins
as Black Infantryman

Corey Sorenson
as Pilot

Hunter Burke
as Soldier

Jamarion Scott
as Little James Brown

Jordan Scott
as Little James Brown

Rena DeAngelo
as Reno Reporter

Aakomon Jones
as Bobby Bennett

George Quinones
as Lynched Man

Aaron Jay Rome
as Frankie Avalon

Atkins Estimond
as Big Junior

Clyde Jones
as Daddy Grace

Michael Papajohn
as 1949 Cop

Denzel Reed
as Big Kid

Phyllis Montana LeBlanc
as Mrs. Byrd

Taura Cherne
as Sarah Byrd

Kirk Bovill
as Announcer

Cariella Smith
as Diner Waitress

Jacinte Blankenship
as Velma Brown

Sandra DeNise
as Female in Audience

Sheldon Frett
as Susie's Soldier

Mario J. Radford
as JB Chauffeur

Joe T. Blankenship
as Alan Leeds

Randy Smith
as Minder

Alvin Edney II
as Teddy Brown

Adrien Scott Robinson
as Little Christmas Boy

Elliott June Rogers
as Little Christmas Girl

Jamell Richardson
as Jimmy Nolen

Jason Davis
as Mayor White

Justin Hall
as Bootsy

David Carzell
as Catfish

Dominic Thigpen
as Chicken

Matt Thompson
as 1949 Cop

Aaron J. Brooks
as Insurance Agent