The Real Madrid defender says it is fun to tease the Portugal star in the dressing room about defeats.
The Portugal star has been in sensational form this season for Los Blancos, firing 45 goals in all competitions as Carlo Ancelotti's side chases a possible treble.
Ronaldo has spoken in the past of how he would become upset as a youngster should his side suffer defeat, while he was famously moved to tears following the Euro 2004 final loss to Greece, and Varane says that even today Ronaldo's teammates will tease him over any kind of setback.
"Ronaldo is a bon vivant, he is friendly, he always has something to help you progress," Varane, 20, told Canal Plus. "He wants to be the best around. It infuriates him when he loses, he cannot stand it. It's true that sometimes, in the dressing room, it's fun to lose just to make him mad!"
Varane, who joined the Spanish giants in 2011, says players such as Ronaldo have helped him to improve at the Santiago Bernabeu — although he feels it is vital he has taken strides to impose himself upon the team.
"It happens naturally," he said of the ease at which he integrated into the side. "You have to be humble and learn from the players around you. They have the experience, they know the very highest level, they have international caliber. You have to respect them, but not too much. You have to impose yourself."