Ibrahimovic netted 50 goals in 51 appearances for PSG last season to help the French giants secure a second successive quadruple, before leaving on a free transfer to join Manchester United.
PSG have struggled for consistency in the opening months of the 2016-17 campaign, and Emery has conceded that the loss of the experienced Swede is still being felt at the club.
"When I arrived, I was told a lot about Zlatan Ibrahimovic. It's normal, he was one of the best players in the club's history. I think we are learning to play without him," Emery told reporters.
Ibrahimovic joined PSG from AC Milan in the summer of 2012 and netted 156 goals in 180 appearances for the French giants before moving to the Premier League.