More than 500 counterfeit Labubu-style dolls were seized from trade stands at the Royal Welsh Show.
Powys council said the fake toys posed “serious” safety risks for children, including choking hazards and some contain banned chemicals.
The elf-like collectable dolls, from Chinese toy maker Pop Mart, have become hugely popular with children and teenagers in recent years after launching in 2015.
The council urged parents and collectors to be “vigilant” and issued advice on how to spot fakes.
The toys have gone viral on social media, with stars like Rihanna, Dua Lipa, Kim Kardashian, and K-pop group Blackpink’s Lisa among their fans.
The craze has also fuelled a rise in dangerous counterfeits, posing serious risks to buyers.
At the show in Llanelwedd, near Builth Wells in Powys, the fake toys were seized by the council’s Trading Standards Service, which carried out spot checks to ensure that products being sold, especially toys, met legal safety standards.
The council said genuine Labubu dolls come in a matte-finish box with a smooth texture, include a QR code linking to Pop Mart’s website and have nine teeth and pale peach-toned faces.
It also said they featured soft fur and seamless stitching, a Pop Mark logo on the right foot and a UV-visible stamp on the left.
