The Algerian president ruled against abolishing a regulation that women require permission from a family member or guardian to marry.
"It is a grave discrimination against women, who will remain minors for life," Miriam Bilaala, president of the rights group SOS Women in Distress, said. "The long-awaited family code reform will now mean little to Algerian women."
Analysts say Boutaflika's decision not to drop the guardian clause from an amendment to the 1984 family code he approved on Tuesday showed religious groups still carried weight after a long-running uprising against a military coup that has claimed the lives of 150,000 people.
The uprising was sparked by the cancellation of elections by the military, in which the Islamic Salvation Front (FIS) party was set to win by an overwhelming majority in 1992, and was subsequently banned.
The amendments will now go to parliament for approval and are expected to pass given the support Boutaflika enjoys.
Amnesty International said recently that Algeria's laws legitimised discrimination, facilitated violence and made it hard for women to protect themselves from rights abuses.
Another Algerian women's rights group said it would campaign to completely abolish the family code and replace it with a civil code.
Algeria was once seen as a champion of women rights in the Middle East after its women fought alongside men in the war of independence against France.