The U.S. Department of Defense identified the missing civilian contractor as 60-year-old Issa T. Salomi and said he was last seen Jan. 23.
In the video, the man says his abductors from the League of the Righteous are demanding the release of militants and the prosecution of Blackwater security contractors accused of killing 17 Iraqis in 2007.
He also says the group is demanding the immediate withdrawal of the U.S. military from Iraq.
The U.S. military in Baghdad on Saturday confirmed Salomi is missing but would not give additional information.