SUNDAY Mail editor Edmund Kudzayi's application to be removed from remand was thrown out by a Harare magistrate on Tuesday.
Kudzayi, together with his brother, Phillip, are being charged with terrorism and banditry.
Prosecutors allege that the two ran a controversial Facebook page dubbed Baba Jukwa that encouraged Zimbabweans to rise against President Robert Mugabe's government in the run-up to last year's elections.
The faceless Baba Jukwa page provided sensitive information on what was happening in Cabinet and top Zanu PF meetings, much to the embarrassment of the ruling party.
In his ruling Tuesday, magistrate Milton Serima said the state needed to be accorded enough time to conclusively investigate the case.
"The accused persons have been on remand for a reasonable time considering the complexity and nature of the matter. State should be afforded more time to complete its investigations," Serima said.
For the pair, legal counsel Admire Rubaya argued that the state was taking too long in furnishing a trial date thereby denying his clients' freedom.
Prosecutor Sharon Mashavira successfully made an application for the matter to be postponed to October 3, upon which investigations are expected to have been completed.
Mashavira on Monday indicated that the state needed more time to carry out extra-territorial investigations by visiting US-based companies Facebook and Google.
The Kudzayi brothers are facing allegations of plotting insurgency, banditry, sabotage and terrorism against a constitutionally elected government.
They are also accused of "hatching a plan" to unseat Mugabe's government through unconstitutional means.
The state says Edmund, together with some accomplices calling themselves the Gunda-Nleya Brigade and the Zimbabwe Revolutionary Army, plotted to overthrow Mugabe if he rigged the July 31 election.
Meanwhile, charges against the duo have been combined with those of another accused in the matter, Romeo Tanyaradzwa Musemburi, 20.
Musemburi is a University of Zimbabwe economics student. He was arrested on June 30 following investigations into the saga.
He is being accused of posting on the Baba Jukwa page statements inciting violence against the state.
His post read, "We want guns, give us guns and we will hit the streets and fight for democracy".