Drogba struck both goals in their 2-2 draw at Atletico Madrid last night.
"Didier is an important player for us. We have a lot of important players but he is doing very well and we are happy," said Ancelotti, who did not feel that Drogba was necessarily extra motivated to do well tonight.
"He was motivated at the start of the season and has been doing very well and continues to do very well, and I hope he can play in other games like he did tonight," said Ancelotti, whose side face a huge match with Manchester United this weekend.
"He is in a good moment, I'm very happy. I hope he can continue."
When asked if he was currently the best striker in the world, Ancelotti replied: "I want to keep him and I don't to change him with another striker."