The Czech international joined the Stamford Bridge side from Rennes in 2004, making his debut during the Portuguese manager's first spell in charge of the club.
Speaking at his pre-match press conference, Mourinho said: "Petr came here very, very young and immediately, first game of the season, Chelsea-Man United, clean sheet. The book is full of clean sheets and the guy is fantastic. His work ethic is amazing.
"We have the best goalkeeper in the world and the best young goalkeeper [in Thibault Courtois] in the world. I don't think many people disagree with me. If somebody disagrees it will not be by far.
"Our goal is safe and financially we are also very safe because their value in the market is the value of the best. We don't have a problem. Teams with a problem are teams without good goalkeepers."
Cech is expected to make his 300th appearance during Chelsea's game against Cardiff City tomorrow.