The centre-back says that the Real Madrid coach has always been interested in the happenings at the Premier League club despite parting company in 2007.
"We keep in touch by text message, wishing each other luck," Terry told Marca. "He always looks out for our results, and keeps interested in all that happens at the club. He also keeps in touch with Lampard and other players."
Terry added that he would welcome the return of Mourinho to Chelsea with open arms.
"Mourinho and the fans have a great relationship because with him we won the Premier League and some other trophies," he said. "It is important, and for me too, to show respect to Real Madrid because he has a contract there.
"For me personally it is difficult to go into this subject, but the fans have shown clearly that he is a man that they love, above all for what he won, and for pushing the club in a direction it had never gone in before. He is still the Special One."
Mourinho has been at Madrid since the summer of 2010.