List of unmade monster films

The following is a list of unmade Godzilla and related Toho projects, divided by the companies that intended to produce them and listed in chronological order.

Note: This list may not be complete due to projects becoming very obscure or never being fully revealed to the public.

Showa era

• The Ghostly Whale That Came from the Sea to Attack Tokyo (1952, Pre-Godzilla concept by Eiji Tsuburaya)
• The Giant Monster from 20,000 Miles Under the Sea (1953, Pre-Godzilla concept by Eiji Tsuburaya)
• Project G (1954, early concept for Godzilla)
• The Volcano Monsters (1957, failed US revision of Godzilla Raids Again)
• Bride of Godzilla (1956)
• Continuation: King Kong vs. Godzilla (1963, direct sequel to King Kong vs. Godzilla)
• Frankenstein vs. The Human Vapor (1963)
• Frankenstein vs. Godzilla (1964, became Frankenstein vs. Baragon and Mothra vs. Godzilla)
• Giant Monster Attack (1966, became Space Amoeba)
• Operation Robinson Crusoe: King Kong vs. Ebirah (1966, became Ebirah, Horror of the Deep and King Kong Escapes)
• Batman vs. Godzilla (1966, became Batman)
• Two Godzillas: Japan S.O.S.! (1967)
• All Monsters Attack Directive (1968, became Destroy All Monsters)
• Godzilla vs. The Mutant Starfish (1972, better known as Godzilla vs. Hitodah)
• Godzilla vs. Hedorah 2 (1972)
• Godzilla • Redmoon • Erabus • Hafun: Extraterrestrial Monsters a.k.a. Godzilla vs. Redmoon (1974)
• Godzilla vs. the Space Monsters: Earth Defense Directive (1972)
• The Return of King Ghidorah (1972, a.k.a. King Ghidorah's Great Counterattack!, became Godzilla vs. Gigan)
• Jet Jaguar vs. Megalon (1972/1973)
• Godzilla vs. The Megalon Brothers: The Undersea Kingdom's Annihilation Strategy (1973)
• Giant Monsters Converge on Okinawa! Showdown At Zampamisaki (1974, also known as Mechanical Monster Garugan)
• Showdown in Zanpamisaki: Godzilla vs. Mechagodzilla (1974)
• Terror of Mechagodzilla (1975, early script draft / original version)
• S.O.S. Japan! Godzilla's Suicide Strategy (1976)
• Gods of Godzilla a.k.a. Super Godzilla: God's Angry Messenger (Late 1970's)
• Nessie (1978)
• U.S.-Japan Collaboration: Godzilla (1978)
• King of the Monsters: Rebirth of Godzilla (1978)
• A Space Godzilla (1978-1979, separate concept from 1994's Godzilla vs. SpaceGodzilla)
• Godzilla vs. Asuka Fortress a.k.a. Godzilla vs. the Asuka Fortress (1979)
• The Resurrection of Godzilla (1980, became The Return of Godzilla)
• Godzilla 2: Godzilla vs. Biollante (1985-1989, original version of Godzilla vs. Biollante)
• Godzilla 2: Godzilla vs. The Robot Army (1985-1989, became Gunhed)
• Godzilla vs. Ankyron (1985-1989, replaced with Godzilla vs. Biollante, later adapted into Godzilla vs. Destoroyah)
• Untitled animated Godzilla film (1988)

Heisei era

• Mothra vs. Bagan (1990)
• Godzilla vs. King Kong (1990, became Godzilla vs. Mechani-Kong before being scrapped)
• Godzilla vs. Mechani-Kong (1990)
• The Return of King Ghidorah (1992, replaced with Godzilla vs. Gigamoth)
• Godzilla vs. Gigamoth (1992, became Godzilla vs. Mothra)
• Godzilla vs. MechaMothra (1993)
• Godzilla vs. Berserk (1993, became Godzilla vs. Mechagodzilla 2)
• Godzilla vs. Mechagodzilla 2 (1993, early draft versions)
• Godzilla vs. AstroGodzilla (1994, became Godzilla vs. SpaceGodzilla)
• Godzilla (1994, American production)
• Godzilla vs. Ghost Godzilla (1995, replaced with Godzilla vs. Barubaroi, then Godzilla vs. Destoroyah)
• Godzilla vs. Bagan (1995, possibly planned according to Takao Okawara)
• Godzilla vs. Barubaroi (1995, replaced with Godzilla vs. Destoroyah)
• Yamato Takeru II (1997)
• Godzilla vs. Baragon (1999)

Millennium series

Godzilla Reborn (2001, sequel to Godzilla 2000: Millennium)

• Godzilla vs. Kamacuras (2001, original vision for Shusuke Kaneko's Godzilla film)
• Godzilla vs. M, also known as Godzilla vs. Uchujin (2001) - early draft for Shusuke Kaneko's Godzilla film)
• Godzilla X Varan, Baragon and Anguirus: Giant Monsters All-Out Attack (2001, became Godzilla, Mothra and King Ghidorah: Giant Monsters All-Out Attack)
• Godzilla vs. Deathla (2003-2005, became Godzilla 3D to the MAX)
• Godzilla 3D to the MAX (2007-2009, replaced with Godzilla (2014))

Reiwa era

• Hedorah vs. Midora, a.k.a. Hedorah 2 (2014-2017)
• Shin Hedorah (2016-2017, Yoshimitsu Banno project)
• Matango remake (2016, Steven Soderbergh project)
• Shin Godzilla Strikes Back (2018)

International collaborations

• Godzilla: King of the Monsters 3-D (1983)
• Godzilla, a.k.a. Godzilla vs. the Gryphon (1994, replaced with Godzilla (1998))
• GODZILLA 2 (1999-2000, sequel to GODZILLA (1998) succeeded by Godzilla: The Series)
• American Godzilla Reboot (2000-2003) - a new American Godzilla film considered by Sony prior to them losing the rights to Godzilla in 2003; not connected to GODZILLA (1998).
• Godzilla (2012) (became Godzilla (2014))

Unproduced television series

• Toho Special Effects Terror-Beast Series: Zone The Meteor Man - Production Memo (1972)
• Toho Monster TV Film Project: Zone The Meteor Man (1972)

Miscellaneous projects and deleted sequences

• Star Godzilla (1980, unauthorized Hong Kong production)
• Rodan (NES video game, 1991)
• Godzilla and the Lost Continent (late 1990's)
• Godzilla vs. Terminator (Dark Horse Comics, 1990's)
• New Golden Bat, AKA The Golden Bat: Millennium Version (unsold anime pilot, 2000's)
• Godzilla vs Cthulhu (IDW Publishing, 2010)
• Creature At Bay (television series / pilot script, 2013)