Customs officers seized a stash of 315 smartphones, worth a total of HK$820,000, from a truck leaving Hong Kong via the Lok Ma Chau control point on Friday.
The truck was intercepted by officers from the special task force and the Lok Ma Chau division acting on a tip-off.
The driver claimed he was transporting 184 cartons of batteries, plastic beans and integrated circuits.
But after an X-ray examination, the smartphones - including Apple iPhone 4s and other top brands - were found hidden inside two false compartments in the driver's cabin.
The driver, 25, was arrested and the lorry was seized.
A total of 25 similar smuggling cases, involving HK$14 million of goods, have been detected this year. Hong Kong Customs and Excise said there was a big demand for hi-tech electronic products.
Anyone taking new mobile phones or computers back to the mainland has to pay 20 per cent tax, whether the devices are for their own use or not.
Apple's latest smartphone, the iPhone 5, has been hotly sought after by mainland users since its launch on Friday in nine markets, including Hong Kong.
Parallel traders bought the phones from customers as they left Apple's Central store for HK$3,000 more than the official retail price, planning to resell them over the border.