The two combined at one end with the German's goal giving the Gunners a 1-0 win at Fulham on Saturday, while they helped keep a clean sheet at the other.
The duo have received many plaudits for their recent performances together and the Frenchman feels that they have a positive influence on one another.
"[Mertesacker and I] play well together as a pair," Koscielny told ESPN. "We communicate on the pitch well.
"His experience is vital and it helps us work together on the pitch, so we try and talk to each other a lot and it is important at the back to have an understanding. Per is a very good player. He reads the ball well.
"He is clever, attacks the ball and wins headers whereas I can go behind and be quick and cope with the long balls. He is good technically so he is good for the defence. Per is calm on the pitch. He is good for me, he uses his experience, this helps me, and he helps the team."
Arsenal host Manchester United on Sunday.