Romantic relationships, reciprocated or not.
- Lois Lane, Superman's wife
- Lana Lang, Clark Kent's childhood romance
- Wonder Woman, often paired with Superman romantically
- Lori Lemaris, Clark Kent's college sweetheart
- La Encantadora
- Big Barda, forced into making an adult film
- Dana Dearden
- Maxima, finds Superman worthy of fathering a child
- Luma Lynai
- Chloe Sullivan
- Lyla Lerrol
- Lyra 3619
- Loana, mother to Van-El in the Superman: The Animated Series version of "For the Man Who Has Everything."
- Cat Grant, dated Clark Kent
- Orella, almost married in Superman #180 (October 1965)