[more detailed list here]

2003 Hominids by Robert Sawyer

2002 American Gods by Neil Gaiman

2001 Harry Potter and the Goblet of Fire by J.K. Rowling

2000 A Deepness in the Sky by Vernor Vinge

1999 To Say Nothing of the Dog by Connie Willis

1998 Forever Peace by Joe Haldeman

1997 Blue Mars by Kim Stanley Robinson

1996 The Diamond Age by Neal Stephenson

1995 Mirror Dance by Lois McMaster Bujold

1994 Green Mars by Kim Stanley Robinson

1993 TIE: A Fire Upon the Deep by Vernor Vinge, Doomsday Book by Connie Willis

1992 Barrayar by Lois McMaster Bujold

1991 The Vor Game by Lois McMaster Bujold

1990 Hyperion by Dan Simmons

1989 Cyteen by C.J. Cherryh

1988 The Uplift War by David Brin

1987 Speaker for the Dead by Orson Scott Card

1986 Ender's Game by Orson Scott Card

1985 Neuromancer by William Gibson

1984 Startide Rising by David Brin

1983 Foundation's Edge by Isaac Asimov

1982 Downbelow Station by C.J. Cherryh

1981 The Snow Queen by Joan D. Vinge

1980 The Fountains of Paradise by Arthur C. Clarke

1979 Dreamsnake by Vonda N. McIntyre

1978 Gateway by Frederik Pohl

1977 Where Late the Sweet Birds Sang by Kate Wilhelm

1976 The Forever War by Joe Haldeman

1975 The Dispossessed by Ursula K. Le Guin

1974 Rendezvous with Rama by Arthur C. Clarke

1973 The Gods Themselves by Isaac Asimov

1972 To Your Scattered Bodies Go by Philip José Farmer

1971 Ringworld by Larry Niven

1970 The Left Hand of Darkness by Ursula K. Le Guin

1969 Stand on Zanzibar by John Brunner

1968 Lord of Light by Roger Zelazny

1967 The Moon Is a Harsh Mistress by Robert A. Heinlein

1966 TIE: Dune by Frank Herbert, This Immortal by Roger Zelazny

1965 The Wanderer by Fritz Leiber

1964 Way Station by Clifford D. Simak

1963 The Man in the High Castle by Philip K. Dick

1962 Stranger in a Strange Land by Robert A. Heinlein

1961 A Canticle for Leibowitz by Walter M. Miller, Jr.

1960 Starship Troopers by Robert A. Heinlein

1959 A Case of Conscience by James Blish

1958 The Big Time by Fritz Leiber

1957 [no novel award]

1956 Double Star by Robert A. Heinlein

1955 They'd Rather Be Right (aka The Forever Machine) by Frank Riley and Mark Clifton

1954 [no awards given]

1953 The Demolished Man by Alfred Bester