The Spain international believes the reigning champions can still do better and has urged his teammates to keep their feet on the ground after the win against Real Madrid.
The Blaugrana beat their archrivals 2-1 at Camp Nou on Saturday to make it nine wins from their opening 10 La Liga games, yet Iniesta has insisted that they have room for improvement.
"We still have to hit top form. The team has to keep on improving over the season in order to be in the running for titles," Iniesta told Barca TV.
The Catalans hold a one-point lead over Atletico Madrid at the moment, while Madrid are already trailing by six points, but Iniesta has stressed that nothing has been decided yet.
"At this stage of the season it’s not definitive as there’s a long way to go. It’s true that matches against Madrid have something extra, an extra motivation," he added. "On Tuesday [against Celta Vigo] there are another three points in play and if we don’t win that match, what we have done against Madrid won’t mean anything. We have to enjoy it and savoxr it, and then think about Vigo."