Al Pacino

Officer Frank Serpico

John Randolph

Sidney Green

Jack Kehoe

Tom Keough

Biff McGuire

Captain McClain

Barbara Eda-Young

Laurie

Cornelia Sharpe

Leslie Lane

Tony Roberts

Bob Blair

John Medici

Pasquale

Allan Rich

D. A. Tauber

Norman Ornellas

Rubello

Edward Grover

Lombardo

Albert Henderson

Peluce

Hank Garrett

Malone

Damien Leake

Joey

Joseph Bova

Potts

Gene Gross

Captain Tolkin

John Stewart

Waterman

Woodie King Jr.

Larry

James Tolkan

Steiger

Ed Crowley

Barto

Bernard Barrow

Palmer

Sal Carollo

Mr. Serpico

Mildred Clinton

Mrs. Serpico

Nathan George

Smith

Gus Fleming

Dr. Metz

Richard Foronjy

Corsaro

Alan North

Brown

Lewis J. Stadlen

Berman

John McQuade

Kellogg

Ted Beniades

Sarno

John Lehne

Gilbert

M. Emmet Walsh

Gallagher

George Ede

Daley

Charles White

Delaney

F. Murray Abraham

Detective Partner (uncredited)

Don Billett

Detective Threatening Serpico (uncredited)

P.J. Benjamin

Man (uncredited)

Val Bisoglio

Weapons Storage Officer (uncredited)

James Bulleit

Det. Styles (uncredited)

Roy Cheverie

Cop (uncredited)