Doctor Doom is a supervillain appearing in American comic books published by Marvel Comics. Created by Stan Lee and Jack Kirby, the character first appeared in The Fantastic Four #5 (1962), and has since endured as the archenemy of the superhero team the Fantastic Four.

Victor Werner von Doom is the monarch of the fictional European country of Latveria who uses his mastery of both science and sorcery in pursuit of his goals to bring order to humanity through world domination, and prove his intellectual superiority over Mister Fantastic—his old college rival and the leader of the Fantastic Four. Doom blames Mister Fantastic for his disfigurement, and wears a magically forged suit of armor with a metal mask and green hooded cloak to conceal his facial scars. Regarded as one of the smartest characters and most dangerous threats in the Marvel Universe, Doom has stolen the abilities of cosmic beings such as the Silver Surfer and the Beyonder in his lust for power, although his pride and arrogance frequently lead to the failures of his schemes of conquest. While his primary obsession is the Fantastic Four, Doom has also fought other heroes, including Spider-Man, Iron Man, Doctor Strange, Black Panther, the X-Men, and the Avengers.

The character has been adapted in various media incarnations, including films, television series, and video games. Joseph Culp, Julian McMahon, and Toby Kebbell have portrayed Doom in the live-action Fantastic Four films, and Robert Downey Jr. plays the character in the Marvel Cinematic Universe (MCU) franchise.

Like many of Marvel's Silver Age characters, Doom was conceived by Stan Lee and Jack Kirby. With the Fantastic Four title performing well, Lee and Kirby were trying to dream up a "soul-stirring...super sensational new villain" for the series. Looking for a name, Lee latched onto "Doctor Doom" as "eloquent in its simplicity — magnificent in its implied menace."

Due to the rush to publish, the character was not given a full origin story until Fantastic Four Annual #2, two years after his debut.

In a 1987 interview, Kirby commented on Doctor Doom's design. "Dr. Doom was the classic conception of Death, of approaching Death. I saw Dr. Doom as The Man in the Iron Mask, who symbolized approaching Death. It was the reason for the armor and the hood. Death is connected with armor and inhuman-like steel. Death is something without mercy and human flesh contains that element of mercy. Therefore, I had to erase it, and I did it with a mask."

Kirby further described Doom as being "paranoid", wrecked by his twisted face and wanting the whole world to be like him. Kirby went on to say that "Doom is an evil person, but he's not always been evil. He was [respected]...but through a flaw in his own character, he was a perfectionist." At one point in the 1970s, Kirby drew his interpretation of what Doom would look like under the mask, giving Doom only "a tiny scar on his cheek". Due to this slight imperfection, Doom hides his face not from the world, but from himself. To Kirby, this is the motivation for Doom's vengeance against the world; because others are superior due to this slight scar, Doom wants to elevate himself above them. Stan Lee's writing typically showed Doom's arrogance as his constant downfall, and how his pride leads to von Doom's disfigurement at the hands of his own machine, and to the failures of many of his schemes.

While the Fantastic Four had fought various villains such as the Mole Man, Skrulls, the Miracle Man, and Namor the Sub-Mariner, Doom managed to overshadow them all and became the Fantastic Four's archnemesis. During the 1970s, Doom branched out to more Marvel titles such as Astonishing Tales, The Incredible Hulk, and Super-Villain Team-Up (1975). Beginning with issue #42, he also had appearances in Marvel Team-Up (February 1976). Doom's origin was also a feature in Astonishing Tales when his ties to the villain Mephisto were revealed.