The 26-year-old Swede was linked with a move away from the Scottish Premier League champions during last season.
"I have two more years here then we'll see what happens," Sky Sports News quotes him as saying. "I'm happy, though, and I like Celtic as a club and Glasgow as a city.
"Celtic are bigger than I thought they'd be when I signed. You see how much it means to the people when you come here."
Lustig joined the Hoops from Rosenborg in 2011.