Man-Bat (Dr. Robert Kirkland "Kirk" Langstrom) is a fictional character appearing in American comic books published by DC Comics. Introduced in Detective Comics #400 (June 1970) as an enemy of the superhero Batman, the character belongs to the collective of adversaries that make up his rogues gallery. Originally portrayed as a supervillain, later incarnations show the Man-Bat as a sympathetic villain or antihero.

In the original version of the story, Kirk Langstrom was a zoologist who tried to give humans a bat's acute sonar sense. He managed to develop an extract that could supposedly do this. Upon testing it on himself, he transformed into an anthropomorphic feral half-bat hybrid, lacking sapience and acting purely on instinct. Batman managed to reverse the effects, but Langstrom would return as the Man-Bat time and time again, albeit not necessarily as a villain, as Langstrom would sometimes retain enough sanity to use his powers for good. Several other characters have since appeared as similar Man-Bat creatures, including Langstrom's wife Francine, his father Abraham Langstrom, and some League of Assassins operatives that make up the Man-Bat Commandos.

Since his debut at the end of the Silver Age of Comic Books, the Man-Bat has been featured in various media adaptations, including television series and video games. In 2017, the Man-Bat was ranked as IGN's 16th-best Batman villain.

The character made his first appearance in Detective Comics #400 (June 1970) and was created by Frank Robbins and Neal Adams in collaboration with editor Julius Schwartz. The Man-Bat was the star of his own eponymous series in 1975–1976, which proved to be unpopular and was cancelled after only two issues.

Dr. Kirk Langstrom, a zoologist who specializes in chiropterology, develops an extract intended to give humans a bat's acute sonar sense and tests the formula on himself. The extract works, but it has a horrible side effect: it transforms him into a monstrous human/bat hybrid creature. This side effect makes him so distraught that it temporarily affects his sanity. He goes on a mad rampage until Batman finds a way to reverse the effects. Later, Langstrom takes the concoction again and the Man-Bat returns. He also coaxes his wife, Francine Langstrom, into drinking the serum and she goes through the same transformation, becoming the She-Bat. Together, they terrorize Gotham City until Batman once again restores them to normal.

On some occasions, Langstrom takes the serum and retains enough sanity to work for the forces of good. During one of these periods, he works with the detective Jason Bard. On another occasion, in Action Comics #600, Jimmy Olsen inadvertently puts Superman into a cave occupied by the Man-Bat to protect him from kryptonite radiation. The Man-Bat calms the maddened Superman and then summons Hawkman, who helps Superman overcome the radiation. Kirk and Francine have a daughter, Rebecca ("Becky"), and a son, Aaron. Because of the effects the serum has on Aaron's DNA, he is born with a deadly illness. Francine turns him into a young Man-Bat to save his life. This occurs in issue #3 of the Man-Bat (vol. 2) miniseries by Chuck Dixon.

The Man-Bat is sighted in Alexander Luthor Jr.'s Secret Society of Super Villains during the events of the 2005–2006 storyline Infinite Crisis.

In the aftermath of that storyline, both Kirk and Francine are shown to be alive in the 2006 "One Year Later" storyline. Talia al Ghul binds and gags Francine, and then threatens to poison her if Kirk does not give her the Man-Bat Serum. After Langstrom gives her the formula, she releases Francine as promised. Talia utilizes the Man-Bat to turn some generic members of the League of Assassins into Man-Bat Commandos.