Zamora's goals helped fire Fulham into the 2010 Europa League final and he spent four years at the club before moving to QPR in January 2010.
Redknapp despairs at the way modern-day football supporters abuse the players they once cheered - and he hopes Zamora gets the reception he deserves.
"I don't know why you should get stick when you go back to a club where you have done so fantastically well," Redknapp said.
"Why do you abuse someone when they have given you good service and been a good player? I went to watch them play Juventus that night (in the Europa League). That was one of the best footballing nights I have ever been to.
"Fulham went 1-0 down and they were something like 4-1 down on aggregate (but came back to win 4-1 on the night) and Bobby ripped them to pieces.
"What a night of football, I loved every minute of it.
"Years ago people would go back to their old club and they would get a lovely ovation. Dear oh Lord, what has happened?"