Ron Howard Richie Cunningham Actor Henry Winkler Arthur "Fonzie" Fonzarelli Actor Tom Bosley Howard Cunningham Actor Marion Ross Marion Cunningham Actor Anson Williams Warren "Potsie" Weber Actor Don Most Ralph Malph Actor Erin Moran Joanie Cunningham Actor Al Molinaro Al Delvecchio Guest Star Scott Baio Al Delvecchio Guest Star Lynda Goodfriend Lori Beth Allen Guest Star Penny Marshall Laverne DeFazio Guest Star Cindy Williams Shirley Feeney Guest Star F. William Parker Vernon Guest Star Vicki Frederick Helga Guest Star April Clough Inga Guest Star Jerry Paris Director