Ex-army general Nazifa Zaki, dressed in a casual black Afghan dress and head scarf, began arguing with fellow MP Hamida Ahmadzai and then threw a water bottle at her in anger, in footage broadcast by private TV station Tolo News.
A stunned Ms Ahmadzai chucked a bottle back towards Ms Zaki, who then launched herself at Ms Ahmadzai, trying to grab her around the neck and delivering a series of punches to her face as lawmakers gathered for the morning session.
Ms Ahmadzai tried to fight back as male MPs rushed in to break up the scrap.
MPs were mostly tight-lipped over the embarrassing incident that took place as British Prime Minister David Cameron visited the capital Kabul and held talks with President Hamid Karzai over peace talks with the Taliban.
One MP, speaking on condition of anonymity, said the pair rowed over the reputation of Vice President Mohammad Kasim Fahim, one of Afghanistan's most powerful warlords and alleged to have been involved in crime and corruption.