Bellion has found first team opportunities limited at Old Trafford and Alex Ferguson was keen for him to gain some first team experience.
Alan Pardew spoke about the signing, “David is in the same mould as several other young players we have developed in recent years.
“The Club has enjoyed outstanding success with players like Matthew Etherington, Nigel Reo-Coker, Anton Ferdinand and Mark Noble.
“David is 22 and will reinvigorate the right hand side of our attack and give me a whole new set of options.
“He is the sort of player that can break a deadlock with his pace as he is without question one of the quickest players in the Premiership.
“With all my recent signings I have looked for pace, people who are good on the ball and who will play the stylish brand of football West Ham fans demand. David fits all those criteria.
who was loaned to West Brom last season and broke into the England team.”