The club have made the surprise move to part company with the Portuguese boss, despite sitting 10 points clear at the top of the Greek Super League
The news has come as a major surprise, with the club currently 10 points clear at the top of the Greek Super League, boasting an unbeaten league record, and through to the last 32 of the Europa League.
The club's official statement read: "Olympiakos announces the termination of its co-operation with coach Leonardo Jardim and thanks him for his services to the club."
Owner Vangelis Marinakis has criticised the team in recent weeks for a defensive style of play and it appears the final straw for was Wednesday's narrow 1-0 victory over second division side Kavala, in the Greek Cup.
The statement also confirmed that former Thrylos and Greece goalkeeper Antonios Nikopolidis will take charge of the side for the time being, before the club name Jardim's permanent successor.
Olympiakos begin life without the Portuguese on Sunday when they take on PAS Giannina at Karaiskakis stadium.