The 26-year-old helped the Foxes win the Premier League title last season, scoring twice in 38 matches.
He joined them on a free transfer from Aston Villa in July 2014.
Albrighton told the club website: "The club have been great to me since I signed. I've had some amazing times here and we've reached the ultimate by winning the league last year."
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Leicester City midfielder Marc Albrighton has signed a new four-year deal.