| Star Quest | 1968 |
| Fear That Man | 1969 |
| The Fall of the Dream Machine | 1969 |
| The Dark Symphony | 1969 |
| Hell's Gate | 1970 |
| Dark of the Woods | 1970 |
| Beastchild | 1970 |
| Anti-Man | 1970 |
| The Crimson Witch | 1971 |
| Warlock | 1972 |
| Time Theives | 1972 |
| Starblood | 1972 |
| The Flesh in the Furnace | 1972 |
| A Darkness in My Soul | 1972 |
| The Haunted Earth | 1973 |
| Demon Seed | 1973 |
| A Werewolf Among Us | 1973 |
| Hanging On | 1973 |
| After the Last Race | 1974 |
| Nightmare Journey | 1975 |
| Night Chills | 1976 |
| The Vision | 1977 |
| Whispers | 1980 |
| Phantoms | 1983 |
| Dark Fall | 1984 |
| Twilight Eyes (Original) | 1985 |
| Strangers | 1986 |
| Twilight Eyes (Expanded) | 1987 |
| Watchers | 1987 |
| Lightning | 1988 |
| Midnight | 1989 |
| The Bad Place | 1990 |
| The Servants of Twilight (Twilight) | 1990 |
| Cold Fire | 1991 |
| Hideaway | 1992 |
| Dragon Tears | 1993 |
| Mr. Murder | 1993 |
| Trapped (graphic novel) | 1993 |
| Winter Moon | 1994 |
| Dark Rivers of the Heart | 1994 |
| Icebound | 1995 |
| Chase (Revised) | 1995 |
| The Key to Midnight (Revised) | 1995 |
| Intensity | 1995 |
| Ticktock | 1996 |
| Demon Seed (Revised) | 1997 |
| Sole Survivor | 1997 |
| False Memory | 1999 |
| From the Corner of His Eye | 2000 |
| The Paper Doorway | 2001 |
| One Door Away From Heaven | 2001 |
| By the Light of the Moon | 2002 |
| The Face | 2003 |
| Every Day's a Holiday | 2003 |
| Life is Good (with Trixie Koontz) | 2004 |
| The Taking | 2004 |
| Robot Santa | 2004 |
| Life Expectancy | 2004 |
| Christmas is Good (with Trixie Koontz) | 2005 |
| Velocity | 2005 |
| The Husband | 2006 |
| The Good Guy | 2007 |
| The Darkest Evening of the Year | 2007 |
| Your Heart Belongs To Me | 2008 |
| Nevermore (graphic novel w/Keith Campagne) | 2009 |
| Relentless | 2009 |
| Breathless | 2009 |
| What The Night Knows | 2010 |
| 77 Shadow Street | 2011 |
Moonlight Bay Series |
|
| Fear Nothing | 1998 |
| Seize the Night | 1999 |
Odd Thomas Series |
|
| Odd Thomas | 2003 |
| Forever Odd | 2005 |
| Brother Odd | 2006 |
| Odd Hours | 2008 |
| In Odd We Trust | 2008 |
Dean Koontz's Frankenstein |
|
| Prodigal Son | 2005 |
| City of Night | 2005 |
| Dead and Alive | 2008 |
| Lost Souls | 2010 |
| The Dead Town | 2011 |
| Frankenstein: Prodigal Son/City of Night (omnibus) | 2011 |
Collections and Omnibus |
|
| Soft Come the Dragons/Dark of the Woods | 1970 |
| Three Complete Novels | 1991 |
| Winter Moon/Icebound | 1995 |
| Strange Highways | 1995 |
| Koontz I | 1996 |
| Koontz II | 1996 |
| Koontz III | 1997 |
| Key To Midnight/Shattered/House of Thunder | 1998 |
| Cold Fire/Key To Midnight/Hideaway | 2001 |
| Dark Rivers of the Heart/Sole Survivor/Intensity | 2001 |
| The Paper Doorway: Funny Verse and Nothing Worse (poems) | 2001 |
| Every Day's A Holiday: Amusing Rhymes for Happy Times (poems) | 2003 |
| The Book of Counted Sorrows (poems) | 2003 |
Picture Books |
|
| Oddkins | 1988 |
| Santa's Twin | 1996 |
| I, Trixie, Who Is Dog | 2009 |
| Trixie and Jinx | 2010 |
Non-Fiction |
|
| Writing Popular Fiction | 1972 |
| How to Write Best Selling Fiction | 1981 |
| Bliss To You: Trixie's Guide To A Happy Life (w/Trixie Koontz) | 2008 |
| A Big Little Life: A Memoir of a Joyful Dog | 2009 |
Anthologies |
|
| "A Mouse in the Walls of the Global Village" - Again, Dangerous Visions 2 | 1972 |
| Time Thieves and Against Archturus | 1972 |
| The Edge of Never | 1973 |
| Final Stage | 1974 |
| "Drown in the Darkness" - The Architecture of Fear | 1987 |
| Night Visions Hardshell | 1987 |
| "Trapped" - Stalkers | 1989 |
| Between Time and Terror | 1990 |
| "The Interrogation" - Obsessions | 1991 |
| "Twilight of the Dawn" - Masters of Darkness III | 1991 |
| "Hardshell" - Predators | 1993 |
| Predators | 1993 |
| "The Undercity" - Cyber-Killers | 1997 |
Short Stories |
|
| "Kittens" | 1966 |
| "Beastchild" | 1970 |
| "Dark of the Moon" | 1970 |
| "Nightmare Gang" | 1970 |
| "Soft Came The Dragons" | 1970 |
| "Bruno" | 1971 |
| "Ollie's Hands" | 1972 |
| "Time Thieves" | 1972 |
| "Night of the Storm" | 1974 |
| "We Three" | 1974 |
| "The Black Pumpkin" | 1986 |
| "Snatcher" | 1986 |
| "Miss Attila The Hun" | 1987 |
| "Strange Highways" | 1995 |
Written as Leigh Nichols |
|
| The Key to Midnight | 1979 |
| The Eyes of Darkness | 1981 |
| The House of Thunder | 1982 |
| Twilight (The Servants of Twilight) | 1984 |
| Shadowfires | 1990 |
Written as Owen West |
|
| The Fun House | 1980 |
| The Mask | 1981 |
Written as David Axton |
|
| Prison of Ice | 1976 |
Written as Leonard Chris |
|
| Hung! | 1970 |
Written as Aaron Wolfe |
|
Laser Book Series |
|
| Invasion (#9) | 1975 |
Written as Brian Coffey |
|
| Blood Risk | 1973 |
| Surrounded | 1974 |
| The Wall of Masks | 1975 |
| The Voice of the Night | 1980 |
Written as Richard Paige |
|
| The Door to December | 1985 |
Written as John Hill |
|
| The Long Sleep | 1975 |
Written as K.R. Dwyer |
|
| Chase (Original) | 1972 |
| Shattered | 1973 |
| Dragonfly | 1975 |
| The Face of Fear | 1977 |
Written as Deana Dwyer |
|
| Demon Child | 1971 |
| Legacy of Terror | 1971 |
| Children of the Storm | 1972 |
| Dance with the Devil | 1972 |
| The Dark Summer | 1972 |
Written as Anthony North |
|
| Strike Deep | 1974 |