The style icon posed with the young boy, named Hudson, in one of the stunning changing rooms at the new space in London's Mayfair.
"Hudson, my youngest customer so far! x VB," she tweeted, sharing the Instagram photo posted by Hudson's mother.
Victoria Beckham posed with little Hudson at her newly opened flagship store in London
Victoria was the epitome of laidback chic for the impromptu visit of her store, in a black jumper paired with some leopard print trousers.
Leaving her sleek hair down and opting for a smokey eye for some daytime glamour, Victoria completed the look with a pair of her trademark black stiletto heels.
The adorable little boy is seen beaming as he poses alongside Victoria. "Thank you so much @victoriabeckham," his fashion blogger and stylist mum captioned the photo. "Beautiful store. #hudsonwithvictoria #victoriabeckham."
It seems apt that the pair posed in one of the changing rooms, as Victoria had previously revealed that she had designed them with motherhood in mind.
"When I shop, I've always got at least one child with me," she told the Evening Standard. "So my fitting rooms I wanted to make sure there's somewhere to put your shopping, something to put your child."
The 40-year-old designer has visited her store on a number of occasions since it opened last Thursday. Braving the British weather for her first visit, she channelled business chic in a black, midi-length skirt and open neck white shirt.
To complete her monochrome look, she added some black suede ankle boots and a clutch bag.