The Welsh manager also named former Inter Milan and Argentina defender, Javier Zanetti, as the hardest player he has played against.
The 46-year-old had a glittering playing career at Man United, winning thirteen English Premier League titles and two UEFA Champions Leagues over a successful 24-year period at Old Trafford.
“The best player I played with is Cristiano Ronaldo,” Giggs told Man United TV.
“Obviously he was only there for a short space of time, and he was brilliant for United and then went on to do even better elsewhere. Or not even better just as well as United.
“Scholesy is the best player I have played with at United, and you have all seen it in training you could not get near him.
“His brain was just quicker than everyone else, his range of passing, nasty.
“You think you have got him and he will just pop it off and give it the little feint. He was just brilliant in training.”
Giggs added: “The hardest player I have played against was Zanetti for Inter Milan. He just ran all day.
“He used to play in midfield, so he was comfortable on the ball.
“He could defend, he was tough, and he actually broke my nose once. Zanetti had everything as a defender.”