Whitney Houston's Estate Denies Oprah's Claim Singer Was High on Her Show

Whitney Houston's estate is pissed about Oprah Winfrey claiming the late singer showed up to her talk show high on drugs, and they say what happened that day is actually Oprah's fault ... TMZ has learned.

Whitney's estate, run by Pat Houston, tells TMZ in a statement ... Pat "emphatically responds to a statement made by Oprah Winfrey at Cannes Lions."

Pat added ... "Whitney absolutely fell off the stage, but it was during a sound check, and it was due to the darkness of the area and her unfamiliarity with the stage. She was absolutely not high."

She acknowledges Whitney's addiction struggles, saying ... "Like many people, she faced personal battles, but it is inaccurate and unfair to attach that struggle to every performance or every chapter of her life. What the studio audience witnessed on stage was the result of discipline, talent, and commitment --- not the assumptions others project."

Pat ended, "Whitney’s humanity included triumphs and struggles, but on that day, she showed up as the professional and gifted artist she always worked to be. We owe her the dignity of telling the truth, not repeating myths."

As we previously reported, Oprah was receiving Cannes' LionHeart Award at the France's Lumière Theatre when she told the audience about Whitney's 2009 appearance, her final visit to Oprah's show.

During her revelation, O claimed Whitney had recently relapsed ... and was so high that day she fell off the stage.

Oprah says she begged the audience not to take photos or say a word about the fall, because she said it would ruin Whitney's life.