The Senegal international has signed a five-and-a-half-year deal with the Magpies and arrives at St James' Park for an undisclosed fee.
Saivet, who can play as a winger or in central midfield, has been with Bordeaux since he was a teenager but will now make his new home in England's north east having appeared 178 times for Les Girondins.
25-year-old Saivet told Newcastle's official website: “I am very happy to be here at Newcastle.
“I am really proud to be able to play for this Club, and I am really excited at the challenge that lies ahead.
“St. James' Park is a really impressive and special stadium. In France there is nothing that compares to this, and I can't wait to get out there with my new teammates and help the team climb the table."
SAIVET SIGNS: Senegalese midfielder signs five-and-a-half-year deal at St. James' Park https://t.co/5vCeEURu7n#NUFCpic.twitter.com/VwLfy3SLjn
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