Iron Man's premiere was a collaboration among editor and story-plotter Lee, scripter Lieber, story-artist Heck, who would illustrate most of the early Iron Man tales, and Kirby, who provided the cover pencils and designed the first Iron Man armor. Heck created the look of characters including protagonist Tony Stark and his secretary, Pepper Potts. Lee based Stark's personality on Howard Hughes, explaining, "Howard Hughes was one of the most colorful men of our time. He was an inventor, an adventurer, a multi-millionaire, a ladies man and finally a nutcase."

Iron Man starred in generally 13-page but occasionally 18-page adventures, with the rest of Tales of Suspense devoted to anthology science fiction and supernatural stories. After debuting with bulky grey armor, Iron Man was redesigned with similar but golden armor in his second story (issue #40, April 1963), with the first iteration of his familiar, sleek red-and-golden armor appearing in issue #48 (Dec. 1963), drawn by Steve Ditko (though whether he or Kirby, singly or in collaboration, designed it, is uncertain).

Beginning with issue #59 (Nov. 1964), Iron Man began sharing the now "split book" Tales of Suspense with Captain America. After the final issue, #99 (March 1968), the book became Captain America; Iron Man appeared in the one-shot Iron Man and Sub-Mariner #1 (April 1968), and then debuted in his own title with The Invincible Iron Man #1 (May 1968).

Iron Man was originally an anti-communist hero. Throughout the character’s comic book series, technological advancement and national defense were constant themes, but later issues developed Stark into a more complex and vulnerable character as they depicted his battle with alcoholism and other personal difficulties.

Writers often portray Iron Man as a symbol of humanity's creativity as well as its frailties. He is often placed in contrast with his close friends Captain America and Thor, the former as a contrast between interventionist and cooperative attitudes, and the latter contrasting science and the supernatural. Throughout most of his career, Iron Man has been a member of the superhero team the Avengers, and has been featured in several incarnations of his own various comic-book series.