Belgian keeper Courtois, 20, is a Chelsea player on loan at Atletico for a second season and earmarked as the long-term successor to Cech at Stamford Bridge.
Cech said: "When you know the new keeper who is coming, it's better to know the way he plays. It's always interesting to see the other keeper playing so, if I have the chance to watch his games for Atletico, I do.
"He's one of the biggest talents in Europe at the moment. That's why the club paid the money for him and it's great to have the opportunity to have him here."