The 30-year-old striker - capped over 50 times and a star of Algeria's 2014 World Cup finals campaign - spent part of last season on loan at Premier League rivals Newcastle having scored 13 times in 46 appearances for the Foxes since joining from Sporting Lisbon in 2016 for a club record fee of £28million ($35.7million, 31.2million euros).
"Leicester City striker Islam Slimani has joined top flight Turkish club Fenerbahce on loan for the 2018/19 season," read a statement from Leicester.
Slimani joins a Fenerbahçe side that finished second in the Turkish Super Lig last season and began their new campaign with a 2-1 win at home to Bursaspor on Saturday.