Jean-Claude Biver, who heads the French group's luxury-watch division, said the US tech titan had made "some fundamental mistakes" designing the Apple Watch (First Impressions).
(Also see: Apple Watch Unveiled as 'Comprehensive Health and Fitness Companion')
"This watch has no sex appeal. It's too feminine and looks too much like the smartwatches already on the market," Biver said in an interview with daily Die Welt.
"To be totally honest, it looks like it was designed by a student in their first trimester," added Biver, who heads up the brands Tag Heuer, Zenith and Hublot.
Biver predicted the much-anticipated device, with its square face and curved edges, would soon be outdated.
"Luxury always has something timeless, it's rare and conveys prestige," he was quoted as saying, adding that the same could not be said for Apple Watch, which is expected to be bought by millions of customers and will likely be beyond repair in a few years' time.
Biver is not the first watch chief to be dismissive of Apple's efforts. Swatch CEO Nick Hayek earlier told Swiss media that the world's biggest watch group was "not nervous" about Apple's foray into the market.
Apple Watch, which comes in several colours and links to the iPhone, will start at $349 (270 euros) when it is released early next year. The wrist device is the first new product category to be launched by Apple since the death of co-founder Steve Jobs in 2011.
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