Ronaldo has enjoyed a stunning season, scoring 42 goals in just 39 appearances, including 15 in the Champions League.
Varane, thus, is insistent that Ronaldo will make a difference against the German side as Real look to win the competition for the third year in a row.
"I believe that the other forwards can also contribute important goals, although it is true that Cristiano does incredible things," Varane told AS.
"Every time we think he's going to go down a bit, he comes back to pile up a lot of goals.
"With Cristiano we are used to him surprising us year after year."
And Varane believes that a number of supporters want Madrid to fail every year.
"It is evident that there are many people who dream of seeing us fall," he added. "No doubt. However, they are not the majority. We feel the affection of our fans and we know that Madrid is a club adored across the whole world.
"In recent years we are present in the decisive moments of the Champions League and certain people cannot stand it and want to see us lose.
"But that's part of football. I am aware that they are waiting for us against Bayern and that it will be more complicated than last season. But I insist, the critics are not a majority. There are many people who support us."