The prolific Portugal forward was said to be unhappy at Santiago Bernabeu following the departure of the likes of Angel Di Maria and Xabi Alonso.
However, Ronaldo denied being unsettled with the European champions, vowing "my future is with Madrid" and Ancelotti on Friday dismissed talk of the former United man returning to Old Trafford.
"These are words without meaning." he said.
"I believe [the] reports are nonsense. Cristiano is happy here, very motivated to be here, and all Madridismo is delighted with him.
"Ronaldo [has] great professionalism, leadership, we must enjoy him and do everything to keep him in this physical and mental condition.
"Without doubt Ronaldo is the best player in the world. We are lucky he plays for us. We have to enjoy it."
Former Milan coach Ancelotti stated that he has not decided whether Iker Casillas or Keylor Navas will start in goal when Real travel to Villarreal in La Liga on Saturday.
He said: "I'll make my decision after today's [Friday] training. And no, I'm not thinking about starting one keeper at home and another one away.
"If Iker plays, that means he's the best for me. I started Keylor against Elche to give him minutes."
The Italian revealed that defenders Pepe and Fabio Coentrao will play no part due to injury.
