Lampard has found himself under pressure in recent weeks after a poor run of form in the Premier League has seen the Blues slip to ninth in the table, winning only two of their last eight matches.
While pressure is continuing to mount on the Chelsea boss, Merson believes bringing in the experienced Redknapp as part of his coaching team would be invaluable.
"Frank Lampard needs an experienced coach like Harry Redknapp to come in and help him at Chelsea. Someone he can use as a sounding board who isn't a threat to his job but has plenty of knowledge and can give him good advice," Merson told the Daily Star.
"I don't know how Frank hasn't already reached out to someone like that and offered them a role at the club. You can't tell me Ole Gunnar Solskjaer doesn't ring Sir Alex Ferguson for advice at Manchester United. Come on.
"I still think Chelsea should give him time but he needs someone alongside him with more experience than Jody Morris in my opinion. Lampard needs to get it turned around quickly or he'll be out of a job – but I can't help thinking some help from an experienced old head like Harry would help."
Chelsea's next two Premier League matches will see them face Wolverhampton Wanderers and Burnley at Stamford Bridge before an away trip to rivals Tottenham Hotspur in early February. body check tags ::