Customs officers said on Wednesday that they have broken up two online platforms offering bogus brand-name mooncakes.
Officers said they seized 49 boxes of the Mid-Autumn Festival treats valued at about HK$16,000.
Three people, aged between 28 and 51, have been arrested.
Senior Inspector Chow Lai-Man said the fake goods look just like the real products offered by two well-known companies, but there's one way to check their authenticity.
"There is a laser sticker with a QR code printed on it for product authentication. Consumers can use the camera function in their smartphones to scan the QR code, which will then link them to a specific website to verify the authenticity of the product," she said.
"For the suspected counterfeit mooncakes, scanning the QR code will lead to a link to a counterfeit website. The layout of the counterfeit verification result is very different from that of the genuine product.”
Officers said the problematic mooncakes are priced at around 70 to 90 percent of the real products, adding that a government laboratory is now testing them to find out if they contain any harmful substances.