Ghezzal, 26, arrived in Leicester on Friday for a medical and has agreed a four-year contract with the Premier League outfit.
Manager Claude Puel will hope to strengthen Leicester's City's attack after losing star man Riyad Mahrez to champions Manchester City in a deal worth £60m.
Ghezzal has had a difficult season for Monaco after arriving last summer from fellow French side Lyon, struggling to make the starting XI consistently in Ligue 1. The Algerian scored twice and assisted four goals in all competitions last season for the Ligue 1 runners-up.
Leicester kick off their Premier League season at Old Trafford against Manchester United next Friday.