The prosecutor said Ronaldo used shell company in the Virgin Islands to cheat on his taxes.
The 54-year-old Mourinho, who coached Madrid from 2010-13, now coaches Manchester United.
Jose Mourinho is facing allegations of tax fraud in Spain worth almost £3 million.
A prosecutor said he did not declare income from the use of his image rights in order to get an "illicit benefit".
Ronaldo is not the first footballer who has been accused of tax fraud in Spain.
This latest scandal has left the four-time world player of the year's future at the Barnabeu in doubt, as media reports say Ronaldo is unhappy that the Spanish giants did not back him as fully as he had hoped in his dispute with the taxman.
Manchester United have so far made no comment on reports they are interested in buying back the player for an estimated 200 million euros, on top of the release fee. However, Mourinho's representatives last night issued a statement insisting the Spanish government had ratified his tax affairs. Ronaldo and Mourinho are both clients of agent Jorge Mendes.
But tax authorities later found that some of the information presented in that settlement was incorrect, the prosecutors said.
Although Perez said everyone, including Ronaldo, must obey their tax obligations.
Chelsea owner Roman Abramovich is set to capitalize on the unrest between Cristiano Ronaldo and Real Madrid, and is prepared to offer his club's best player (Eden Hazard) in a superstar plus cash deal, expected to be worth somewhere in excess of £150 million.
"From now on it will be the judge in charge of the case who will take the necessary steps to determine the possible responsibilities of Mr Mourinho".
Di Maria, who now plays for French club Paris Saint-Germain, will likely not serve any prison time because sentences of less than two years for first-time offenders are usually suspended in Spain.