Heathcliff

June Foray

Iggy/Muggsy/ Grandma/ Sonja/Marcy

Henry Corden

Clem/Digby/Dogcatcher

Paul Winchell

Marmaduke

Mel Blanc

Heathcliff/Spike/Milkman

Don Messick

Sparerib/ Nobody/ Mr. Post/ Mr. Snyder