| Cover Artist | Curt Swan |
| Editor | Mort Weisinger |
| Inker | Jim Mooney |
| Penciler | Jim Mooney |
| Writer | Jerry Siegel |
| Genre | Superhero |
| Published in | Sparta, Illinois |
| Pages | 80 |
| Characters | Supergirl (Kara Zor-El) (Earth 1), Supporting Characters:, Superman (Kal-El) (Earth 1), Fred Danvers (Earth 1) (First appearance), Edna Danvers (Earth 1) (First appearance), Other Characters:, Krypto (Earth 1), Lori Lemaris (Earth 1), Streaky (Earth 1) (Flashback and main story), Lenora Lemaris (Earth 1) (First appearance), Legion of Super-Heroes (Cameo):, Saturn Girl (Imra Ardeen) (Pre-Zero Hour) (Cameo), Lightning Lad (Garth Ranzz) (Pre-Zero Hour) (Cameo), Brainiac 5 (Querl Dox) (Pre-Zero Hour) (Cameo), Cosmic Boy (Rokk Krinn) (Pre-Zero Hour) (Cameo) |
| Story Location | Atlantis, Midvale: Midvale Orphanage, Antarctica: Fortress of Solitude, Bottle City of Kandor, Krypton (Destroyed in flashback): Argo City (Origin) (Destroyed in flashback), Metropolis, New York: New York City; United Nations Building, Washington, D.C.: White House, 30th Century: Metropolis; Legion of Super-Heroes Headquarters |
| Collects | "The Unknown Supergirl", "Supergirl's Secret Enemy", "Trapped in Kandor", "The Three Red K Perils", "The Super-Mermaid", "The World's Mightiest Heroine", "The Infinite Monster" |
| Links | Issue link · Reprint link · Reprint link · Reprint link · Reprint link · Reprint link · Reprint link |
| Notes | Reprinted Issues:
1st Story: Action Comics Vol 1 #278, July, 1961; "The Unknown Supergirl"
2nd Story: Action Comics Vol 1 #279, August, 1961; "Supergirl's Secret Enemy"
3d Story: Action Comics Vol 1 #280, September, 1961; "Trapped in Kandor"
4th Story: Action Comics Vol 1 #283, December, 1961; "The Three Red K Perils"
5th Story: Action Comics Vol 1 #284, January, 1962; "The Super-Mermaid"
6th Story: Action Comics Vol 1 #285, February, 1962; "The World's Greatest Heroine! Part 1"
7th Story: Action Comics Vol 1 #285, February, 1962; "The Infinite Monster! Part 2" |
