Superman first appeared in Action Comics #1, published in June 1938.
Created by writer Jerry Siegel and artist Joe Shuster, Superman was introduced as a costumed hero with extraordinary strength, speed, and resilience. The issue also established his origin on the planet Krypton and his identity as Clark Kent.
Action Comics #1 is widely regarded as a landmark in comic-book history because Superman helped define the modern superhero genre. The character’s debut is often used as the starting point for the superhero comic-book era.
A common mix-up is confusing Superman’s first appearance with his first self-titled comic. His first solo series, Superman, began in 1939, after his debut in Action Comics.