Tiffany & Co. has received a takeover approach from LVMH Moët Hennessy Louis Vuitton, which is seeking to add the iconic U.S. jeweler to its portfolio of upscale brands.

The French company sent Tiffany officials a letter in the past couple of weeks outlining an all-cash takeover bid of about $120 a share, according to people familiar with the matter. That would value Tiffany at close to $14.5 billion.

LVMH...