The Red Devils host Juventus at Old Trafford to honour the defender, who made 400 league appearances for Sir Alex Ferguson's side after starting out in 1993.
And LA Galaxy midfielder Beckham, a close friend of Neville, told reporters of the "special feeling" he gets when he pulls on the famous shirt.
"Putting a United shirt on again never gets old," said the England international.
"I get goose bumps every time I think about stepping out at Old Trafford again, as does walking out on the pitch."
The 36-year-old midfielder also took time out to pay tribute to Neville, whose testimonial will reunite the famed “class of ‘92” that rose through the youth ranks to dominate English football.
"Gary is still so dedicated," said Beckham. "It is the reason why he has achieved so much in his career and why United fans love him.
"He is a great home-grown talent which United are famous for producing. He always gave me a lot of advice over the years - the majority of which was good. He is such a talent and hard worker. He really deserves this night."
Beckham will play at Old Trafford for just the second time since leaving the club in 2003, having featured for AC Milan against the Red Devils in the Champions League in 2010.
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