Ronaldo left Madrid as their all-time highest goalscorer to join Juventus during last summer transfer window.
Zidane said the Los Blancos will never have a player who can do all that Ronaldo did for the club.
The Frenchman said this ahead of Real Madrid’s La Liga fixture against Leganes on Monday night.
“Cristiano’s situation is one that we can’t change, he’s gone,” Zidane was quoted by Express UK as saying.
“We can sign any player and whoever comes in won’t do all that Cristiano
“That’s the way things go in life, he did some great things at this club and we were delighted with him.
“He’s now in another chapter in his career and I’m tired of repeating myself because we’re not going to win anything at the end of this season but we are going to try and finish strongly.
“We’ve got to try and finish as high up as possible and ahead of the side currently in second, who are Atletico, that’s our aim.”