Leonard Norman Wein (/wiːn/; June 12, 1948 – September 10, 2017) was an American comic book writer and editor best known for co-creating DC Comics' Swamp Thing and Marvel Comics' Wolverine, and for helping revive the Marvel superhero team the X-Men (including the co-creation of Nightcrawler, Storm, and Colossus). Additionally, he was the editor for writer Alan Moore and illustrator Dave Gibbons' influential DC miniseries Watchmen.

Wein was inducted into the Will Eisner Comic Book Hall of Fame in 2008.