Before becoming an editor, Harrison started in the science fiction field as an illustrator, notably with EC Comics' two science fiction comic books, Weird Fantasy and Weird Science. He has used house names such as Wade Kaempfert and Philip St. John to edit magazines, and has published other fictions under the names Felix Boyd, Leslie Charteris, and Hank Dempsey (but see Personal Life below). Harrison also wrote for syndicated comic strips, creating the Rick Random character. Harrison is now much better known for his writing, particularly his humorous and satirical science fiction, such as the Stainless Steel Rat series and the novel Bill, the Galactic Hero (which satirises Robert A. Heinlein's Starship Troopers).

During the 1950s and '60s, he was the main writer of the Flash Gordon newspaper strip. One of his Flash Gordon scripts was serialized in Comics Revue magazine. Harrison drew sketches to help the artist be more scientifically accurate, which the artist largely ignored.

Not all of Harrison's writing is comic, though. He has written many stories on serious themes, of which by far the best known is the novel about overpopulation and consumption of the world's resources Make Room! Make Room! which was used as a basis for the science fiction film Soylent Green (though the film changed the plot and theme).

Harrison for a time was closely identified with Brian Aldiss. The pair collaborated on a series of anthology projects. Harrison and Aldiss did much in the 1970s to raise the standards of criticism in the field.

In 1990 Harrison was professional Guest of Honour at ConFiction, the 48th World SF Convention, in The Hague, Netherlands, together with Joe Haldeman and Wolfgang Jeschke.

Harrison is a writer of fairly liberal worldview. Harrison's work often hinges around the contrast between the thinking man and the man of force, although the "Thinking Man" often needs ultimately to employ force himself.

Harrison was selected by the Science Fiction and Fantasy Writers of America as the 2009 recipient of their Damon Knight Memorial Grand Master Award. Harry Harrison named SFWA Grand Master

Harrison was born Henry Maxwell Dempsey (although he did not know this until he was 30, at which point he legally changed his name to Harry Max Harrison). He was born in Stamford, Connecticut, but has lived in many parts of the world including Mexico, England, Ireland, Denmark and Italy. He is an advocate of Esperanto (the language often appears in his novels, particularly in his Stainless Steel Rat and Deathworld series) and was formerly the honorary president of the Esperanto Association of Ireland, as well as holding memberships in other Esperanto organizations such as Esperanto-USA (formerly the Esperanto League for North America), of which he is an honorary member, and the Universala Esperanto-Asocio (World Esperanto Association), of whose Honorary Patrons' Committee he is a member. He served in the United States Army Air Forces during World War II as a gunsight mechanic and gunnery instructor. He lives in the Republic of Ireland and maintains a flat in Brighton for visits to England.

Harrison married Joan (nee Merkler) in 1954 in New York, a marriage that lasted until her death of cancer in 2002. They have two children, Todd (b. 1955) and Moira (b. 1959), to whom he dedicated the book Make Room! Make Room!.

Novellas

• The Man from P.I.G. and The Man from R.O.B.O.T. (1974) These two linked novellas, featuring interstellar intelligence agents, were comedy-drama take-offs on The Man from U.N.C.L.E. The first tells of an agent of the Porcine Interstellar Guard, who performs his missions with the help of several pigs. The second tells of Henry Venn, an agent for "Robot Obtrusion Battalion ... Omega Three", who poses as an interplanetary robot salesman while searching for a missing Galactic Census official on a planet populated by paranoid colonists. The latter was originally published as a short story in Analog, July 1969.

• Planet Story (1978), published as a large format book with colour illustrations by Jim Burns

Stand-alone novels

• Vendetta for the Saint (1964), credited to Leslie Charteris and based upon Charteris's mystery series, The Saint
• Plague from Space (1965)
• Make Room! Make Room! (1966) - basis for the 1973 science fiction movie Soylent Green starring Charlton Heston
• The Technicolor Time Machine (1967)
• Captive Universe (1969)
• The Daleth Effect (1970) (vt, In Our Hands, the Stars. 1970) (serialised 1969-70 under the latter title)
• Spaceship Medic (1970)
• Tunnel Through the Deeps (1972); vt, A Transatlantic Tunnel, Hurrah!
• Stonehenge (1972) (with Leon Stover) (this was heavily cut from the manuscript, see Stonehenge: Where Atlantis Died (1983))
• Star Smashers of the Galaxy Rangers (1973)
• The California Iceberg (1975)
• Skyfall (1976)
• The Lifeship (variant title: Lifeboat) (1977) (with Gordon R. Dickson)
• The Jupiter Plague (1982); expanded edition of Plague from Space
• Earth (1982)
• The QEII is Missing (1982) (vt, The QE2 is Missing)
• A Rebel In Time (1983)
• Where Atlantis Died (1983) (with Leon Stover) (expanded version reinstating text cut from the original manuscript for the 1972 novel)
• The Turing Option (1992) (with Marvin Minsky)

Tony Hawkin series

• Montezuma's Revenge (1972)
• Queen Victoria's Revenge (1974)

Bill, the Galactic Hero series

1. Bill, the Galactic Hero (1965)
2. Bill, the Galactic Hero on the Planet of Robot Slaves (1989)
3. Bill, the Galactic Hero on the Planet of Bottled Brains (1990, with Robert Sheckley)
4. Bill, the Galactic Hero on the Planet of Tasteless Pleasure (1991, with David Bischoff)
5. Bill, the Galactic Hero on the Planet of Zombie Vampires (1991, with Jack C. Haldeman II)
6. Bill, the Galactic Hero on the Planet of Ten Thousand Bars (1991, with David Bischoff. vt. ...Planet of Hippies from Hell)
7. Bill, the Galactic Hero: the Final Incoherent Adventure (1991, with David Harris)
8. Bill, the Galactic Hero's Happy Holiday (short story in Galactic Dreams) (1994)

Brion Brandd series

• Planet of the Damned (1962) (serialised as Sense of Obligation 1961) (vt Sense of Obligation (1967))
• Planet of No Return (1981)

Deathworld series

On the planet Pyrrus, human colonists have fought a centuries-old war with the native life forms. These life forms adapt to human tactics and technology, evolving new species so rapidly that natives returning from even brief trips off planet must be carried in protective armor canisters from their ship to the safe buildings, where they will learn of the latest deadly threats.

The first three stories were initially published as serials in Analog Magazine under the names given below.

1. Deathworld (1960) (serialised 1960 as Deathworld)
2. Deathworld 2 (1964) (vt, The Ethical Engineer, 1964) (serialised as The Ethical Engineer)
3. Deathworld 3 (1968) (serialised 1968 as The Horse Barbarians)

*The Mothballed Spaceship (1973) ("final" short story, in ASTOUNDING: the John W. Campbell Memorial Anthology).

The following four novels were only published in Russian:

4. Return to Deathworld (1998) (with Ant Skalandis)

5. Deathworld vs. Filibusters (1998) (with Ant Skalandis)

6. The Creatures from Hell (1999) (with Ant Skalandis)

7. Deathworld 7 (2004) (with Mikhail Ahmanov)

• The Deathworld Trilogy (1974, omnibus of Deathworld, Deathworld 2 & Deathworld 3) (vt. The Deathworld Omnibus, 1999) (the BenBella [2005] edition adds the short story `The Mothballed Spaceship' from Astounding: The John W. Campbell Memorial Anthology (1973))

To the Stars trilogy

• Homeworld (1980)
• Wheelworld (1981)
• Starworld (1981)
• To the Stars (1991) - omnibus collection of the three novels

The Stainless Steel Rat series

Main article: The Stainless Steel Rat

Listed according to internal chronology.

1. A Stainless Steel Rat is Born (1985)
2. The Stainless Steel Rat Gets Drafted (1987)
3. The Stainless Steel Rat Sings the Blues (1994)
4. The Stainless Steel Rat (1961)
5. The Stainless Steel Rat's Revenge (1970)
6. The Stainless Steel Rat Saves the World (1972)
7. The Stainless Steel Rat Wants You (1978)
8. The Stainless Steel Rat for President (1982)
9. The Stainless Steel Rat Goes to Hell (1996)
10. The Stainless Steel Rat Joins the Circus (1999)
11. The Stainless Steel Rat Returns (2010)
12. You Can Be The Stainless Steel Rat: An Interactive Game Book 1988 - choose your own adventure style
13. The Adventures of the Stainless Steel Rat (1978) - omnibus collection of The Stainless Steel Rat, The Stainless Steel Rat's Revenge and The Stainless Steel Rat Saves the World
14. A Stainless Steel Trio (2002) - omnibus collection of A Stainless Steel Rat is Born, The Stainless Steel Rat Gets Drafted and The Stainless Steel Rat Sings the Blues

Stainless Steel Rat short stories

• "The Return of the Stainless Steel Rat" (1981)
• "The Fourth Law of Robotics" (1989)
• "The Golden Years of the Stainless Steel Rat" (1992, published in Stainless Steel Visions)

Eden series

• West of Eden (1984)
• Winter in Eden (1986)
• Return to Eden (1989)

The Hammer and the Cross series

In collaboration with "John Holm", a pseudonym of Tom Shippey.

• The Hammer and the Cross (1993)
• One King's Way (1995)
• King and Emperor (1997)
• Warriors of the Way (1995) (omnibus of the first two)

Stars and Stripes trilogy

• Stars and Stripes Forever (1998)
• Stars and Stripes in Peril (2000)
• Stars and Stripes Triumphant (2002)

Short story collections

See List of Harry Harrison Short Stories

• Two Tales and Eight Tomorrows (1965)
• War with the Robots (1967)
• Prime Number (1970)
• One Step from Earth (1970)
• The Best of Harry Harrison (1976)
• Stainless Steel Visions (1992)
• Galactic Dreams (1994)
• 50 In 50 (2001)
• The Men From P.I.G. and R.O.B.O.T.

Comics

• Rick Random with artist Ron Turner (trade paperback: October 2008, ISBN 1853756733)
• Flash Gordon (1958–1964)
• The Stainless Steel Rat (1979-1985) was adapted into a comic strip in the magazine 2000 AD by Kelvin Gosnell, with artist Carlos Ezquerra (trade paperback: July 2010, ISBN 1906735514)
• Harry Harrison's Bill, The Galactic Hero Comics; 3 issues

Non-fiction books

• Great Balls of Fire: A History of Sex in Science Fiction Illustration (1977)
• Mechanismo (1977)
• Spacecraft in Fact and Fiction (1979)

Anthologies (as editor)

• John W. Campbell: Collected Editorials from Analog (1966)
• Nebula Award Stories No. 2 (1967) (with Brian Aldiss) (vt, Nebula Award Stories 1967)
• Apeman, Spaceman (1968) (with Leon Stover)
• Best SF: 1967 (1968) (vt, The Year's Best Science Fiction) (with Brian Aldiss)
• Farewell Fantastic Venus (1968) (abr as vt, All About Venus, 1968)
• SF: Author's Choice (1968) (vt, A Backdrop of Stars)
• Best SF: 1968 (1969) (rev vt, The Year's Best Science Fiction No. 2) (with Brian Aldiss)
• Blast Off: SF for Boys (1969)
• Four for the Future (1969)
• Worlds of Wonder (1969)
• Best SF: 1969 (1970) (vt, The Year's Best Science Fiction No. 3) (with Brian Aldiss)
• Nova 1 (1970) (rev edition 1976, UK hc)
• SF: Author's Choice 2 (1970)
• The Year 2000 (1970)
• Best SF: 1970 (1971) (vt, The Year's Best Science Fiction No. 4) (with Brian Aldiss)
• The Light Fantastic (1971)
• SF: Author's Choice 3 (1971)
• The Astounding-Analog Reader, Volume One (1972) (with Brian Aldiss) (later split into two paperbacks: The Astounding-Analog Reader, Book 1 & The Astounding-Analog Reader, Book 2)
• Ahead of Time (1972)
• Best SF: 1971 (1972) (vt, The Year's Best Science Fiction No. 5) (with Brian Aldiss)
• Nova 2 (1972)
• The Astounding-Analog Reader, Volume Two (1973) (with Brian Aldiss) (only one edition; NOT the same book as The Astounding-Analog Reader, Book 2 above)
• Astounding: The John W. Campbell Memorial Anthology (1973) (vt, The John W. Campbell Memorial Anthology)
• Best SF: 1972 (1973) (vt, The Year's Best S.F. 1972) (with Brian Aldiss)
• Nova 3 (1973) (vt, The Outdated Man)
• A Science Fiction Reader (1973) (with Carol Pugner)
• Best SF: 1973 (1974) (abr vt, The Year's Best Science Fiction No. 7) (with Brian Aldiss)
• Nova 4 (1974)
• SF: Author's Choice 4 (1974)
• Best SF: 1974 (1975) (abr vt, The Year's Best Science Fiction No. 8) (with Brian Aldiss)
• Decade: The 1940s (1975) (with Brian Aldiss)
• Hell's Cartographers: Some Personal Histories of Science Fiction Writers (1975) (with Brian Aldiss) (memoirs by SF writers)
• Science Fiction Novellas (1975) (with Willis E. McNelly)
• Best SF: 1975, The Ninth Annual (1976) (vt, The Year's Best Science Fiction No. 9) (with Brian Aldiss)
• Decade: The 1950s (1976) (with Brian Aldiss)
• Decade: The 1960s (1977) (with Brian Aldiss)
• There Won't Be War (1991) (with Bruce McAllister)