About 99 percent of shareholders voted in favour of the union during a special meeting that was held virtually, a spokesperson told AFP.
The green light was the last step needed to finalize the tie-up scheduled for early January.
The parent to luxury brands such as Louis Vuitton, Dior and Moet & Chandon, LVMH announced its plan to acquire Tiffany and its iconic robin’s egg blue gift boxes at the end of 2019.
But the French company walked away from its proposal in September after claiming a series of poor decisions by Tiffany’s board.
The companies buried the hatchet in October after Tiffany agreed to a lower price to prevent the deal from collapsing.
The price was dropped by $3.50 a share to $131.50, lowering the value of the deal to $15.8 billion from the original $16.2 billion.
LVMH had already obtained authorisation from the authorities for the merger.
Tiffany will be removed from the New York Stock Exchange, but the French company has not yet said how it plans to transform the jeweller, which has suffered in recent years from competition from brands favoured by millennials.