She said existing vetting procedures meant free and healthy elections were not possible.
Ahead of the 17 June presidential election, the Guardians Council, a watchdog which screens all candidates, has said it is sticking by its interpretation of a key word in Iran's constitution that has long been taken as meaning that only men can be president.
"I object to the Guardians Council's interpretation of the word 'rijal'," Ebadi told a news conference in Tehran.
The disputed word "rejal", which comes from Arabic and refers to man (or men), could also be interpreted as meaning "personalities" in Persian and this is the translation used in some English translations of the constitution.
"The approbatory supervision by the Guardians Council ... negates a free and healthy election," said a statement issued by the Defenders of Human Rights Centre, a group headed by Ebadi.
Aside from barring women, the Guardians Council can also weed out candidates it deems to be unsuitable.
This power was used to devastating effect prior to the February 2004 parliament elections, when nearly all pro-reform candidates were disqualified.