The six times Pro Bowl player, who began his career with Minnesota in 1998, has been traded pending his passing a physical examination, the Vikings said on their website (www.vikings.com).
The acquisition gives Vikings quarterback Brett Favre a much-needed receiver.
Pro Bowler Sidney Rice, a favorite target of Favre's in the past, is on the sidelines with a hip injury for at least the first six weeks of the season.
Without a big-play receiver, the Vikings have won only one of three games this season.
"We feel very good about the opportunity to add a player of Randy Moss' caliber," Vikings coach Brad Childress said in a statement.
"He is a tremendous competitor and was an integral member of the Vikings organization from 1998-2004."
In his 13th NFL season, Moss, 33, ranks second in the NFL with 151 career touchdown receptions, fifth with 14,604 career receiving yards and 10th with 935 career receptions.
At New England, he had caught just nine passes for 139 yards and three touchdowns in four games this season. He had 83 catches for 1,264 yards and 13 touchdowns last season.
A first round draft pick in 1998, he had 17 touchdowns for his rookie season and went on to record 90 TD catches during seven seasons with the Vikings.
He also spent two seasons with the Oakland Raiders before joining the Patriots in 2007.
(Reporting by Gene Cherry in Salvo, North Carolina. Editing by Julian Linden)
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