He will join Israel Start-Up Nation for next season as sole team leader.
After 10 years and four Tour de France titles won with Ineos (formerly Team Sky), Froome, 35, said: "We have achieved so much together and I will always treasure the memories."
Froome will compete for Ineos at this year's Tour, which begins on 29 August.
Ineos general manager Sir Dave Brailsford said he and Froome "shared many memorable moments over the years, but I do believe this is the right decision for the team and for Chris".
Read MORE
BBC NEWS