The 26-year-old has 16 caps for Holland and played for Cottagers boss Martin Jol during his time at the Ajax helm.
Emanuelson is a left-sided player that can play at either full-back or in midfield and will stay with Fulham until the end of the 2012-13 season.
"It is not easy to get players from AC Milan on a permanent basis," Jol said of him after Fulham's 3-1 defeat of West Ham. "I coached him at Ajax. He is a skilful player, very agile. He is very mobile, quick.
"He can play left midfield, wide, play number 10 so I feel we need fresh legs."