Leon Russom is Clayton in The Hot Tub (Season 7 - Episode 5).

Leonard Termo is Joe in The Mango (Season 5 Episode 1).

Lewis Arquette is Leapin' Larry in The Secret Code (Season 7 Episode 7).

Lewis Dauber is Doorman in The Watch (Season 4 - Episode 6).

Lili Bernard is Anna in The Wife (Season 5 Episode 17).

Lilian Lehman is Judge in The Scofflaw (Season 6 Episode 13).

Linda Kash is Gwen in The Lip Reader (Season 5 - Episode 6).

Linda Wallem is Hildy in The Soup (Season 6 Episode 7).

Lionel Mark Smith is the flower guy in The Gum (Season 7 Episode 10).

Lisa Deanne Young is Christie in The Seven (Season 7 Episode 13).

Lisa Edelstein is Karen, in two episodes: The Mango (Season 5 Episode 1) and The Masseuse (Season 5 Episode 9).

Lisa Houle is Cheryl in The Non-Fat Yogurt (Season 5 Episode 7).

Lisa Kushell is «Connie» in The Friar's Club (Season 7 Episodes 17).

Lisa Malkiewicz is Sandra in The Cheever Letters (Season 4 Episode 8).

Lisa Mende is Carol in four episodes. The first The Boyfriend 2 (Season 3 Episode 17).

Lisa Pescia is Joanne in three Seinfeld episodes. The first is The Cigar Store Indian (Season 5 Episode 10).

Liz Georges is Pam in The Note (Season 3 Episode 1).

Liz Sheridan is Helen Seinfeld, Jerry's mother. She appears in 21 episodes. The first: The Stakeout (Season 1 Episode 2).

Lloyd Bridges is Izzy Mandelbaun in The English Patient (Season 8 Episode 17) an in The Blood (Season 9 Episode 4).

Lois Nettleton is Mrs. Enright in The Gymnast (Season 6 Episode 6).

Lori Loughlin is Patty in The Serenity Now (Season 9 Episode 3).

Lou Cutell is Dr. Howard Cooperman in The Fusilli Jerry (Season 6 Episodes 21).

Louan Gideon is Mrs. Hamilton in The Millenium (Season 8 Episode 20).

Louis Mustillo is Phil, Jerry's neighbor in The Strongbox (Season 9 Episode 14).

Louisa Abernathy is the nurse in The Kiss Hello (Season 6 Episode 17).

Lucy Lin is Hostess in The Chinese Woman (Season 6 Episode 4).

Lynn Alicia Henderson is Clerk in The Package (Season 8 Episode 5).