Bill Murray
as Peter Venkman

Dan Aykroyd
as Ray Stantz

Sigourney Weaver
as Dana Barrett

Harold Ramis
as Egon Spengler

Rick Moranis
as Louis Tully

Annie Potts
as Janine Melnitz

William Atherton
as Walter Peck

Ernie Hudson
as Winston Zeddemore

Slavitza Jovan
as Gozer

David Margulies
as Mayor

Steven Tash
as Male Student

Jennifer Runyon
as Female Student

Michael Ensign
as Hotel Manager

Alice Drummond
as Librarian

Jordan Charney
as Dean Yager

Timothy Carhart
as Violinist

John Rothman
as Library Administrator

Tom McDermott
as Archbishop

Roger Grimsby
as Roger Grimsby

Larry King
as Larry King

Joe Franklin
as Joe Franklin

Casey Kasem
as Casey Kasem (voice)

John Ring
as Fire Commissioner

Norman Matlock
as Police Commissioner

Joe Cirillo
as Police Captain

Joe Schmieg
as Police Seargeant

Reginald VelJohnson
as Jail Guard

Rhoda Gemignani
as Real Estate Woman

Murray Rubin
as Man at Elevator

Larry Dilg
as Con Edison Man

Danny Stone
as Coachman

Patty Freedman
as Woman at Party

Jean Kasem
as Tall Woman at Party

Lenny Del Genio
as Doorman

Frances E. Nealy
as Chambermaid

Sam Moses
as Hot Dog Vendor

Christopher Wynkoop
as TV Reporter

Winston May
as Businessman in Cab

Tommy Hollis
as Mayor's Aide

Eda Reiss Merin
as Louis's Neighbor

Ric Mancini
as Policeman at Apartment

Kathryn Janssen
as Mrs. Van Hoffman

Stanley Grover
as Reporter

Carol Ann Henry
as Reporter

James Hardie
as Reporter

Frantz Turner
as Reporter

Nancy Kelly
as Reporter

Paul Trafas
as Ted Fleming

Cheryl Birchenfield
as Annette Fleming

Ruth Oliver
as Library Ghost

Kymberly Herrin
as Dream Ghost

Billy Bryan
as Stay Puft Marshmallow Man (uncredited)

Matteo Cafiso
as Boy at Hot Dog Stand (uncredited)

Frankie Como
as T-Shirt Vendor (uncredited)

Peter Costanza
as Man Fleeing Marshmallow Man (uncredited)

John De Bello
as Patrolman Matthews (uncredited)

Paddi Edwards
as Gozer (voice) (uncredited)

Eldo Ray Estes
as Redheaded Man (uncredited)

Brute Force
as Hare Krishna acolyte (uncredited)

Debbie Gibson
as Birthday Girl in Tavern on the Green (uncredited)

Willow Hale
as Student at Columbia University (uncredited)

Jon Hayden
as Library Patron (uncredited)

Ron Jeremy
as Man Behind Barricade (uncredited)

Joseph Marzano
as Man in Taxi (uncredited)

Joe Medjuck
as Man at Library (uncredited)

Danny Nero
as Reporter (uncredited)

Frank Patton III
as City Hall Cop (uncredited)

Harrison Ray
as Terror Dog (uncredited)

Ivan Reitman
as Zuul / Slimer (voice) (uncredited)

Frank Rivers
as Prisoner (uncredited)

Mario Todisco
as Prisoner (uncredited)

Bill Walton
as Bill Walton (uncredited)

Mark Bryan Wilson
as Slimer (uncredited)