The Denmark international, 29, played in all 38 of the Foxes' league fixtures last season, keeping 15 clean sheets.
He has made more than 200 appearances for Leicester since arriving from Leeds United in 2011, having started his career at Manchester City.
"We've taken some massive steps and ever since I arrived it's been fantastic," Schmeichel told LCFC TV.
"It was a case of coming back after winning the Premier League and making sure that the hunger was the same within myself and the squad. I've come back absolutely convinced that this is the place for me to be."
Boss Claudio Ranieri has said the club will not sell anymore of their best players after N'Golo Kante joined Chelsea last month.
England forward Jamie Vardy also signed a new deal with the champions in June, ending speculation that the 29-year-old would join Arsenal.
The Foxes begin their season with the Community Shield at Wembley on Sunday, when they face FA Cup winners Manchester United.
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Inland Fisheries Ireland said the pink salmon, which are of Pacific origin, were found in rivers in Counties Galway, Mayo and Donegal.
The fishing board said it was concerned about the impact the fish may have on Ireland's Atlantic species.
The pink salmon was also found earlier this month in Scotland.
Pink Salmon, also known as humpback salmon, originate from the west coasts of the United States, Canada and northern Asia.
The fish are a favourite prey of North America's grizzly bears.
A potentially invasive species to the UK, the salmon may be related to fish introduced to the Barents Sea in Russia in the 1950s.
The species can be identified by the following characteristics:
However, Dr Greg Forde, head of operations at Inland Fisheries Ireland, said "it seems unlikely that these fish made a migration due to their small size".
He said the appearance of the species was a "mystery".
"We are appealing to the public, and the angling community in particular, to be vigilant and to report any catch of pink salmon to Inland Fisheries Ireland," he added.
Goalkeeper Kasper Schmeichel has signed a new five-year deal with Premier League champions Leicester City.
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A non-native species of salmon has been found in rivers along the west coast of Ireland, causing concern among Irish fishing authorities.