Lampard's form for Chelsea has also come under scrutiny since returning from a groin and hernia injury last December.
Terry told the London Evening Standard: "Frank can still make a massive contribution to England and Chelsea. I think sometimes with the work rate he gets through and the quality of player he is, he gets taken for granted.
"When he doesn't do it for one or two games people jump on the bandwagon. When he does it consistently well for 20-30 games, people don't appreciate him for what he's doing. It's just 'Frank has scored again' and that's it. People are quick to criticise but on a weekly basis he is the most consistent player I have seen in my career at Chelsea.
"I have seen nothing to make me think any differently and am sure he will have another good season next year, hopefully with no injuries."