The couple announced in October their intention to wed but did not say when the ceremony would take place.
Cuoco confirmed she and Resnik had called off their plans during an interview with "Entertainment Tonight" Friday.
Asked if she got any good ideas for her own special day by watching the wedding of her "Big Bang Theory" co-star Kunal Nayyar, Cuoco said: "I'm not engaged anymore, so no. But in general, yes. For my future wedding, yes!"
She did not offer any details regarding when she broke up with her fiance or what caused the split.
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