Since completing his €222 million (£195m/$260m) move to PSG in 2017, the 26-year-old has scored 45 goals and contributed 26 assists in just 50 outings.
But despite the strong attachment Barca's fans had to Neymar during his playing days - which inevitably soured when he left - Iniesta does not expect his former team-mate to return.
"Personally, I see it difficult for him to return, but in football I've seen a hundred thousand things," the Vissel Kobe player, who made over 600 appearances for Barcelona, told RAC 1 .
"If he came back, I've always said for years that he's currently one of the best players in the world.
"And what team would not like to have him. But I cannot imagine him back at Barca."
PSG, however, are confident that despite Neymar's previous with Barca that the world's most expensive player is content with life in Paris.
Speaking earlier this season, coach Thomas Tuchel said: "I think that Neymar feels very, very happy. He is professional, very decisive, with a good state of mind.
"I think he feels good here, both in the locker room and on the pitch. He is disciplined, does a lot on the pitch. You've seen his statistics and what he does in training.
"We are very satisfied with his work. I have the feeling that he wants to show that he is capable of being a leader for PSG, and that's great for us, because on top of that he is one of the best players in the world.
"I have to talk to Neymar, to find out if it's really a good thing to play every game or not. Against Pontivy, he came back into shape, with a good frame of mind, and he wanted to play 90 minutes.
"But now we also have to spare his playing time. With Neymar, I have to take responsibility, because if It was just up to me, he would play every game.
"It's good that he came back earlier, with that state of mind, and that he does not choose his matches. But I'm waiting for him to play like he is 100 per cent in a few weeks, because he's a key player who makes the difference."