Princess Diana’s lucky mascot created quite a buzz.

In a new book, royal protection officer Ken Wharfe reveals how Princess Di was given a vibrator that she dubbed “Le Gadget.”

“The small vibrator, bought as a practical joke after a staff night out in Paris during Diana’s official visit there the previous November, had become her lucky mascot,” Wharfe writes in “Guarding Diana: Protect The Princess Around The World,” the Independent reported.

Di became so attached to her dildo that she insisted on taking it on official foreign trips, he writes.

When she left Le Gadget behind during a trip to Nepal in 1993, she promptly had it delivered to the British Embassy in the capital of Kathmandu.

A Gurkha aid brought the handy device — in a sealed bag — on a silver platter at the ambassador’s residence moments before a press reception.

“Musto, a self-effacing officer who towered over everyone present, not quite knowing what to expect, foolishly opened the packet and removed the offending item in front of everyone in the room (but, mercifully, not the press, who were starting to gather outside),” Wharfe writes.

“There was a stunned pause (and a few bemused glances from Embassy dignitaries), until the silence was broken by Diana, who said, ‘Oh, that must be for me,’ and began to laugh,” he writes.

“Le Gadget was perhaps our finest wind-up, and an almost constant source of laughter,” Wharfe says.

Di’s saucy side also was evident during a tour of Pakistan in 1991, when a member of her entourage inflated a condom over his head, according to the Independent.

“We were all a little demob-happy, when the staff member decided to reveal that he had a party trick where he could blow up the condom and put it on his head, fully inflated,” Wharfe writes.

“’Really? Go on then, show me,’ Diana said, intrigued, and laying down the bizarre challenge excitedly (began),” he says. “Within seconds everyone was falling about the place in fits of giggles as the staff member accomplished this extraordinary feat in a matter of seconds.”

The latest details about the couple’s rocky relationship emerged days after the Sun reported that Di once caught hubby Prince Charles sitting on the toilet having phone sex with his mistress, Camilla Parker-Bowles.

The former guard also addresses the infamous Camillagate conversation that roiled the royal family.

Wharfe said Di triumphantly declared “game, set and match” after reading transcripts of Charles and Camilla’s chat.

The salacious story sent shock waves around the world when the Daily Mirror published the transcripts in 1993 — but Wharfe said the princess was overjoyed by Charles’ public flogging.

“Later, however, she told me that she had been genuinely shocked by some of the baser comments, in particular the Prince’s tampon reference. ‘It’s just sick,’ she said repeatedly,” Wharfe writes.

During the 1989 phone call — which was believed to have been recorded by a radio enthusiast using a scanner — Charles told Camilla that he wanted to “live inside your trousers.”

She responded: “What are you going to turn into, a pair of knickers?” To which he said, “Or, God forbid, a Tampax. Just my luck.”

“The backlash was savage. Establishment figures normally loyal to future King and country were appalled, and some questioned the Prince’s suitability to rule,” Wharfe writes.

Charles was mercilessly lampooned.

“One cartoon, featuring him talking dirty to his plants, particularly amused the Princess, who collapsed into fits of giggles on seeing it,” he writes, according to the Sun.

The transcript was published a month after Charles and Di formally separated. In 2005, he married Camilla, who is now the Duchess of Cornwall.

Wharfe, who guarded Diana from 1987 to 1993, says she was “genuinely upset” when Charles refused to join her at the Taj Mahal in India in 1992.

“The Princess had privately decided to drive home the point,” he wrote about how Di was photographed alone.

Wharfe also describes the cringe-worthy “kiss that missed” episode during that trip, when Diana “intentionally humiliated” Charles by turning her face away as he kissed her.

When he asked her why she had done it, the Mirror reported, she replied: “’Ken, I am not about to pander to him. Why the bloody hell should I? If he wants to make a fool out of me with that woman, he deserves it.’”