The champions are on a run of four straight Premier League defeats and hovering just a point above the relegation places with 14 games to go.
The Italian, who took the Foxes to perhaps the most remarkable Premier League triumph in the league's history last season, recently admitted himself that he was not invincible to the axe.
But in a statement released on Tuesday, Leicester said: "In light of recent speculation, Leicester City Football Club would like to make absolutely clear its unwavering support for its first-team manager Claudio Ranieri.
"While there is a collective appreciation from everyone at the club that recent form needs to improve, the unprecedented success achieved in recent seasons has been based firmly on stability, togetherness and determination to overcome even the greatest of challenges.
"The entire club is and will remain united behind its manager and behind its players, collectively and firmly focused on the challenges ahead."
The Foxes have been struggling in the league all season despite a superb inaugural Champions League campaign that saw them top Group G and qualify for last-16 tie where they face Sevilla on February 22.
Ranieri's side, who are all behind their manager according to right-back Danny Simpson, have not won a top-flight match since New Year's Eve and won only five Premier League games all season.
Manchester City are the only English team ever to be relegated after a top-flight title, winning the league in 1937 but dropping into the old division two in 1938.