The Portuguese enjoyed a highly successful three years at the Stamford Bridge helm before making a shock exit in September 2007.
Now, less than six years on, it seems as if Mourinho will be returning to west London, with a summer move from Real Madrid heavily mooted.
Lampard was an integral member of the side that enjoyed so much success under Mourinho and would welcome the 'Special One's' return.
"I think it would be a great thing for the club," he said. "He is a successful manager and he would be a great thing for any club.
"It's hard to comment with the season still ongoing and with the manager not here or chosen yet. It would be easy to speculate.
"I have seen speculation before and a completely different manager walks through the door so you never know on that front.
"But he is certainly one of the greatest if not the greatest manager in world football."