Embu Governor Martin Wambora becomes the third governor to have his victory nullified by the High Court.
On Tuesday, High Court sitting in Homa Bay nullified Governor Cyprian Awiti's victory with Wajir's Mohammed Abdi facing a similar fate in January.
In January, Embu High Court Judge William Musyoka ordered vote recount following application by Ex-Senator Lenny Kivuti.
"I find there is sufficient basis for ordering a scrutiny in selected centers where grounds are overwhelming," he ruled in an application that was objected by Wambora.
During the August elections, Wambora garnered 97,760 votes to Kivuti's 96,775 votes in one of the closely contested gubernatorial race.
In his Thursday ruling, Judge Musyoka said: "The elections were marred with irregularities thus were not free and fair. I therefore recall the victory of second respondent."
While both candidates are close allies of President Uhuru, Wambora contested on a Jubilee ticket while Kivuti ran on Alfred Matua's Maendeleo Chap Chap.
Throughout his first term, Wambora faced corruption charges that led to his impeachment twice by the senate, a decision that would be quashed by the High Court.