Podolski signed for the Gunners this summer in an £11m deal from FC Cologne.
Mertesacker believes that his German international colleague can be a big success at the Emirates with the help of his new teammates.
He said: "Lukas will need good teammates to make his life as easy as possible. I am someone he can turn to as I've known him for some time.
"We want to fight for trophies. We are up for it and what we want is to come out of the season and know we have given our best."
Germany manager Joachim Low has left the Arsenal duo out of his squad for Wednesday's international against Argentina so that the pair can concentrate on playing for Arsenal against Sunderland on Saturday.