The Barclays Premier League club have yet to confirm the news but Wasilewski has posted a picture on his Instagram account saying: "Today, I signed a new contract at #LCFC".
It is understood that the Krakow-born centre-back, who turns 35 next week, has penned a one-year extension at the King Power Stadium.
Wasilewski, who has won 60 caps for Poland and played at both Euro 2008 and 2012, joined Leicester in September 2013 after six seasons at Belgian club Anderlecht.
The veteran played an important role in Leicester's battle to avoid relegation in the closing months of the Premier League season and has now made over 60 appearances for the Foxes.
Leicester manager Nigel Pearson has spoken highly of the rugged Wasilewski in the past, saying: "I love him, he's great.
"Centre-backs who enjoy defending are a dying breed.
"He is an exceptionally honest professional who knows the game.
"He is a good player as well
I am not saying he is just an honest player and tough, he is a very knowledgeable defender."
Source : PA
Source: PA