N'Koulou, who joined Marseille from Monaco in 2011, has quickly emerged into one of the best defenders in Ligue 1.
However, the Swede told Telefoot: "N'Koulou, who is that? I don't know him. Never heard of him. This is not a lack of respect, but when I don't know a player, I don't know him."
Ibrahimovic has scored eight goals in six games for PSG this season.