The names of the dead have not been released, but officials confirmed the chopper went down Monday outside the city of Kandahar. The five dead included everyone aboard the UH-60 Black Hawk, according to authorities.
NATO said the crash happened in an area where there was no enemy activity. The cause of the crash is under investigation.
Monday night's crash brought the total number of U.S. troops killed that day to seven, making it the deadliest day for U.S. forces so far this year.
Two U.S. special operations forces were gunned down hours earlier in an insider attack by an Afghan policeman in eastern Afghanistan.
The Associated Press contributed to this report.