Hydro-Man (Morris "Morrie" Bench) is a supervillain appearing in American comic books published by Marvel Comics. Created by writer Dennis O'Neil and artist John Romita Jr., the character first appeared in The Amazing Spider-Man #212 (January 1981). Hydro-Man is a recurring antagonist of the superhero Spider-Man.

Once an ordinary crewman, Morris Bench was accidentally knocked overboard while stationed on his ship during a battle between Spider-Man and Namor, and fell into the ocean, where a powerful experimental generator was being tested. This led to his transformation into Hydro-Man who, blaming Spider-Man for what happened to him, turned to a life of crime while seeking revenge against the web-slinger.

The character has appeared in several media adaptations over the years, including animated series and video games. A creature based on "Hydro-Man" appeared in the Marvel Cinematic Universe film Spider-Man: Far From Home (2019).

The Morris Bench version of Hydro-Man made his first appearance in The Amazing Spider-Man #212 (January 1981) and was created by writer Dennis O'Neil and artist John Romita Jr.

Morris "Morrie" Bench gained his superpowers while working as a crewman on the cargo ship the U.S.S. Bulldog, having been knocked overboard accidentally by Spider-Man (right after the hero finished a fight against Namor) while a powerful experimental generator is being tested in the ocean. The combination of unknown radiation and his immersion in a deep ocean-dwelling bacteria turns him into Hydro-Man. When he realized that he had become a man-of-water, he blamed Spider-Man for his accident and started to hunt him (through many showers, sewers and water valves), in order to get revenge on the hero, but was defeated in combat.

Soon after that in the story arc "Eye of the Beholder", he teams up with and briefly becomes merged with the Sandman into a composite mud monster called Mud-Thing. In this form, Hydro-Man and Sandman had limited intelligence and abilities. Although it was composed of the two aforementioned villains, it showed no indication of either villain's persona outside of an infatuation with Sadie Frickett, the current love interest of both villains.

Soon after, a theater agent named Travis Rave proposed that Sadie and Mud-Thing be in a show, which Sadie gladly accepted at the prospect of stardom. Unfortunately, when the show proved to be a huge success, Sadie accidentally kissed Travis out of excitement, thereby enraging the jealous Mud-Thing. Mud-Thing ended up going on a rampage and carried Sadie with him to the top a sky-scraper. The creature was eventually defeated with a special gas that dried it out and caused it to crumble apart. Spider-Man managed to save Sadie from her plummet, but she ended up being genuinely upset over the loss of Mud-Thing, knowing that all it had ever done wrong was simply love her. After its defeat by Spider-Man and the police, Sandman and Hydro-Man separated from this form when the police were cleaning up Mud-Thing's remains. Months later, Hydro-Man and Sandman managed to separate themselves. Hydro-Man departs through the sewer telling Sandman that he will be going south for a while.

Hydro-Man joined supervillain teams such as the Sinister Syndicate, and the Frightful Four. While working with the Sinister Syndicate, Hydro-Man demonstrates a willingness to put up with just about anything in the name of financial gain. He ignores the constant politicking of the other members and looks past the Beetle's betrayal of the group to the Kingpin in the belief that the group was economically beneficial to him. Hydro Man was a member of Crimson Cowl's Masters of Evil, and battled the Thunderbolts. After the disintegration of the group, he began to cooperate with the Shocker. He was hired by Green Goblin to be part of his Sinister Twelve to help kill Spider-Man, but he was defeated again.