Parvin Ardalan, Jelveh Javaheri, Maryam Hosseinkhah and Nahid Keshavarz were sentenced over articles in "Change For Equality" and "Zanestan" websites, their lawyer Nobel peace laureate Shirin Ebadi was quoted as saying in the Korgozaran newspaper.
The four are active members of an initiative that seeks to change Iran's Sharia-based laws for women by collecting one million signatures.
Ardalan, who won Sweden's Olof Palme Prize in 2007, already faces another six-month jail term and suspended sentences of two and two and half years — which are being appealed — on charges of seeking to harm national security.
The 41-year-old campaigner was detained along with 70 other people for a June 2006 demonstration in Tehran square demanding equal rights for women on divorce, inheritance and child custody.
Hosseinkhah, 27, and Javaheri, 30, were also arrested in November and December 2007 for allegedly spreading lies and propaganda against the system over articles written on feminist websites.
The two were released on bail after over a month in jail.
Iran has exerted mounting pressure on women's rights advocates, and several have been arrested in the past year for calling for changes to Iranian laws or for taking part in public protests.
Iran's new family law, which is yet to be debated by the parliament, has also angered women's rights advocates who say it facilitates polygamy.
