The American journalist appeared veiled and weeping in the video broadcast by Aljazeera on Monday night. Her voice could not be heard on the tape but Aljazeera said she called for US forces and the Iraqi Interior Ministry to release all women in their custody.
It was the first glimpse of Carroll since her kidnappers released a video on 17 January in which they threatened to kill her within 72 hours if women prisoners were not released. The deadline had passed with no word on her fate.
"We will not make concessions to terrorist demands," US military spokesman in Iraq Lieutenant Colonel Barry Johnson said. The United States says it does not negotiate with kidnappers or terrorists.
He said US forces were continuing to work with Iraqi authorities "to resolve the situation as quickly as possible".
US and Iraqi soldiers have staged several raids on homes and a mosque in their hunt for her.
The US military released five women prisoners last week, but both they and Iraqi officials insisted the move had been pre-planned and was not linked to the hostage-takers' demands.
US forces say they continue to hold at least four more women security detainees. The Iraqi government has been pressing for the release of the women; the detention of women offends Iraqis and the US military seeks to avoid it in most cases.
"The American journalist kidnapped in Iraq urged her family and Americans around the world to demand that US military forces and the Iraqi interior (ministry) release all Iraqi women prisoners," Aljazeera said on Monday.
"We will not make concessions to terrorist demands"
Lieutenant Colonel Barry Johnson,
US military spokesman
Carroll, 28, a freelance journalist working for the Christian Science Monitor, was abducted in Baghdad on 7 January by gunmen who also killed her Iraqi interpreter on the spot.
There has been a spate of kidnappings of foreigners in Iraq over the past few months after a lull during most of 2005.
Four Christian peace activists - a Briton, an American and two Canadians - are still being held captive, as are two Kenyan engineers and a Jordanian embassy driver.
Carroll is the 31st journalist kidnapped in Iraq since the start of the war in March 2003, according to Paris-based Reporters Sans Frontieres, a media advocacy group.