It said Cristina, 49, had failed to pay a €2.7 million ($3 million) court bond to cover her liability in the case. It ordered her to hand over a list of her assets with a view to impounding them.
Cristina Federica de Borbon y Grecia is the first member of Spain's royal family ever to be sent to the dock. A date has yet to be set for her trial.
In a written ruling Monday, Judge Jose Castro said the deadline for the bond, ordered in December, had long passed and Cristina still had not paid it.
He ordered her and 10 other defendants to present within three days details of their "current accounts, deposits, financial assets and real estate".
Cristina, whose official title is the Infanta, is accused of taking part in tax evasion by her husband, the former Olympic handball player Inaki Urdangarin.
Cristina's lawyers say she is innocent of any wrongdoing and that she trusted her husband to handle their financial affairs.
Urdangarin is accused along with a former business partner of creaming off six million euros in public funds from contracts awarded to Noos, a charitable foundation which he chaired.
Public prosecutors had called on the court to shelve the case, saying there was not enough evidence against Cristina. They hinted that investigators were out to get the princess.
The so-called Noos scandal has fanned public anger against the ruling class during the recent years of economic hardship in Spain.
It soured the reign of Felipe's father Juan Carlos, who gave up the throne in June 2014 after 39 years, hoping his son could freshen up the image of the monarchy.