The England left-back will make his first appearance for the London club for over a month in Wednesday night's UEFA Champions League Group E clash with Steaua Bucharest at Stamford Bridge.
Cole, who turns 33 next week, has been forced to watch on from the substitutes' bench as Mourinho has preferred Cesar Azpilicueta at left-back.
The former Arsenal man's contract is due to expire at the end of the season, but Mourinho has no doubt Cole still has a future at the club.
He said: "I know him well, it’s easy to feel he’s not happy with the situation but the way he trains and behaves, he's a super professional.
"He’s a fantastic guy, full of respect of me and the players and he will start tomorrow (against Steaua).
"Naturally with the evolution of the season, he will play in matches, Can he recover or not 100 per cent his position? I don't know. But he will always play and he will always be a good player.
"I think sometimes even if you are not playing every game and not first choice player like he was always, I don't think it means you are not well and not deserving a new contract and tomorrow he will show he is fine.
"Naturally he will get his contract because he is a valuable player for us."
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