The former England midfielder has spent a month at The City Ground but Forest boss Joe Kinnear decided not to keep him for a further month.
"I would like to thank Nicky for all his efforts during his time with us a wish him well for the future," said Kinnear.
Barmby scored once in his six appearances for Forest but Kinnear can now make another two loan singings after his departure.
Barmby will be hoping that his recent first-team action will help his chances of making it into the first team squad at Leeds.