Drogba, 34, is set to leave Stamford Bridge when his current contract expires in June and recent goal-scoring displays in the semi-finals of the Champions League and FA Cup, against Barcelona and Tottenham respectively, have proven he still has a lot to offer.
Redknapp said: "He would be a great player for Chelsea to keep or for somebody else to take. Anyone would be interested but you would have to be able to afford his wages. That is going to be the key. If he is on a free you are going to have to pay him a fortune.
"But he is a powerhouse when he is on his game. He is strong and almost unplayable when he is really at it. It was an amazing goal he scored against us [in the 5-1 FA Cup semi-final win]. He smashed it from an angle.
"His strength in holding William Gallas off and then hitting the ball from where he did, there aren't too many players who could have done that.''
Despite his admiration of Drogba, Redknapp still expects the Ivory Coast international to move to China to join former Chelsea team-mate Nicolas Anelka at mega-rich side Shanghai Shenhua.
Redknapp said: "He is a free but I was just reading in the paper about him going to China. It seems the money in China at the moment is incredible. Players can go there and make a fortune."