Jerry Seinfeld Jerry Seinfeld Actor, Writer Jason Alexander George Costanza Actor Michael Richards Cosmo Kramer Actor Julia Louis-Dreyfus Elaine Benes Actor Liz Sheridan Helen Seinfeld Guest Star Barney Martin Morty Seinfeld Guest Star Roszika Halmos Manya Guest Star Len Lesser Uncle Leo Guest Star David Fresco Isaac Guest Star Scott N. Stevens Intern Guest Star Earl Boen Eulogist Guest Star Heidi Swedberg Actor Estelle Harris Actor Jerry Stiller Actor Larry David Writer Tom Cherones Director