The Dutch title slipped from Ajax as they were defeated by PSV Eindhoven on a dramatic final day on Sunday 8 May.
De Boer, the man who led Ajax to four straight league titles between 2011 and 2014, has been linked with the 12th placeholder Everton and currently being managed by Roberto Martinez. Frank De Boer has been mentioned as a potential replacement at Everton for Roberto Martínez, whose hold on his job looks fragile after a 3-0 defeat to Sunderland on Tuesday. Everton have won only a single game of their past 10 matches.
The 45-year-old Dutch disclosed in Ajax’s website: “I began to realize that it was time for something else”.
De Boer was in charge of Ajax for the last five and a half year.
Ajax needed to win against De Graafschap, who is at second-from-bottom, to secure the title for the fifth time in six years. Surprisingly they held to a 1-1 draw allowing PSV to claim the league title.
After the game, Frank De Boer said: “It was our own fault, we had it in our hands”.
Edwin van der Sar, the ajax director, said that De Boer is “hugely ambitious”.
“We are sorry that he is leaving. It is not known yet what he will do, but we wish him every success in his future endeavors.” said the former Manchester United keeper.