The 22-year-old, who only joined Sporting Lisbon from Utrecht in the summer, is believed to have caught the eye of United boss Sir Alex Ferguson following a string of goalscoring performances.
However, agent Louis Laros has poured cold water on the rumours, insisting that the striker is happy with life in Portugal.
"Ricky is very well at Sporting, very happy," Laros told A Bola. "He likes the club, the city, the academy and the fans a lot, everything is perfect for him.
"He has always scored in the clubs where he has played. Sporting's team is very good and his teammates, like Diego Capel and the other wingers, provide him with many assists.
"It is a collective effort, not just his own."
Van Wolfswinkel has scored four goals in six appearances for Sporting.