In cable TV, nothing goes to waste.

If Oprah Winfrey tapes an interview for her cable channel, OWN, with Kim Kardashian and family, then the Kardashians are going to tape Oprah taping them for their own cable series, “Keeping Up With the Kardashians,”

“Oprah signed the release!” a source told US Weekly.

No word yet on when the talk show host will show up on the Kardashians’ show.

But Oprah got some of her biggest ratings since the death of singer Whitney Houston with her two-part interview with the K klan — nearly a million viewers over consecutive Sunday nights.

An inside source confirmed that Oprah has agreed to let the Kardashians’ film crew record the off-camera moments for the Kardashian’s show on E!

“We were aware there was going to be a [Kardashian] camera crew on the set because they are still filming their current season,” said the source.

“She and Khloé especially hit it off,” the gossip says. “Khloé had her dying laughing.

“It meant so much because [Khloé] loves Oprah.”