Ortega won a fourth successive mandate with all his challengers in jail.
The senior Chamorro is the only person to have beaten Ortega in an election, in 1990.
Her daughter’s court case opened Thursday at a court inside El Chipote prison, where trials have been held since last month for 46 opposition figures arrested since last year.
They include seven presidential hopefuls, including Chamorro who was the first to be arrested to international condemnation.
The independent Human Rights Center of Nicaragua (Cenidh) on Thursday denounced an “exaggerated police presence” around the prison.
“Not satisfied with the illegality of conducting a trial in a prison, they have now also militarized the entire perimeter of the El Chipote judicial complex in an intimidating manner,” it said on Twitter.
Chamorro, under house arrest since June 2, is accused by the state of laundering money, property and assets through a free speech foundation named after her mother.
Prosecutors say money held by the now-defunct foundation was intended to destabilize the government.
A journalist not aligned to any political party, Chamorro also faces a host of other charges including promoting “ideological falsehood.”
She has described Ortega’s government as “a dictatorship capable of anything.”
Also in court Thursday were Chamorro’s driver, Pedro Vazquez, her brother Pedro Joaquin and two former executives of the foundation.
Defense lawyer Maynor Curtis said the trial could last several days.
He said Chamorro has been “isolated” at her home, with only her children allowed to visit, and has not had contact with her lawyers ahead of the trial.
Of the 46 people detained, over 30 have been found guilty so far, with 18 receiving jail sentences ranging from eight to 13 years.