The law, passed last month, says a husband can demand sex with his wife every four days unless she is ill or would be harmed by intercourse - a clause that critics say legalizes marital rape. It also regulates when and for what reasons a wife may leave her home alone.
Women's rights activists scheduled a protest Wednesday attended by mostly young women. But the group was swamped by counter-protesters - both men and women - who shouted down the women's chants.
Some picked up gravel and stones and threw them at the women, while others shouted "Death to the slaves of the Christians!" Female police held hands around the group to create a protective barrier.
The government of President Hamid Karzai has said the Shiite family law is being reviewed by the Justice Department and will not be implemented in its current form. Governments and rights groups around the world have condemned the legislation, and President Barack Obama has labeled it "abhorrent."
Though the law would apply only to the country's Shiites - 10 to 20 percent of Afghanistan's 30 million people - it has sparked an uproar by activists who say it marks a return to Taliban-style oppression. The Taliban, who ruled Afghanistan from 1996-2001, required women to wear all-covering burqas and banned them from leaving home without a male relative.
Shiite backers of the law say that foreigners are meddling in private Afghan affairs, and Wednesday's demonstrations brought some of the emotions surrounding the debate over the law to the surface.
"You are a dog! You are not a Shiite woman!" one man shouted to a young woman in a headscarf holding aloft a banner that said "We don't want Taliban law." The woman did not shout back at the man, but told him: "This is my land and my people."
Women protesting the law said many of their supporters had been blocked by men who refused to let them join the protest. Those who did make it shouted repeatedly that they were defending human rights by defending women's rights and that the law does not reflect the views of the Shiite community.
Fourteen-year-old Masuma Hasani said her whole family had come out to protest the law - both her parents and her younger sister who she held by the arm.
"I am concerned about my future with this law," she said. "We want our rights. We don't want women to just be used."
As the back-and-forth continued, another demonstration of Shiite women who said they support the law began.
"We don't want foreigners interfering in our lives. They are the enemy of Afghanistan," said 24-year-old Mariam Sajadi.
Sajadi is engaged, and said she plans to ask her husband's permission to leave the house as put forth in the law. She said other controversial articles - such as one giving the husband the right to demand sex from his wife every fourth day - have been misinterpreted by Westerners who are anti-Islam.