Both Arsenal and Spurs are unbeaten in five games in the Premier League and go into the derby with 13 points each, with Postecoglou's side second on goal difference while their arch rivals are fourth.
For Spurs, it is their best start to a top-flight season for 57 years. But they have not won at the Emirates in the league for 13 years while Postecoglou is also aware Arsenal won home and away last season.
"People have given me an indication of how they feel about this game and that's great. I've been involved in derbies and one pretty significant one (the Old Firm derby with Celtic)," Postecoglou told reporters on Friday.
"You understand what it means to supporters of both clubs, the significance in terms of the general mood around the place.
"They are a very, very good football side, they had an outstanding season last year and they've strengthened this year. You can see there is a real belief within them. Playing them at their place is going to be a hell of a challenge for us."
Form has rarely been a factor in North London derbies in the past but Postecoglou said experience may play a role with several recruits set to get a taste of the heated rivalry for the first time.
"We have quite a few that haven't played in this fixture. It's not just that it's a derby and it's away from home, but it's the challenge of overcoming a strong opponent as well," he added.
"As much as you want to talk about it, it's the experience that makes you grow. In these fixtures, you allow the players to go out there and hopefully try and get them to express themselves in the best possible way.
"I don't want to put too many restrictions or try and guide them too much as to what to expect."
Having sold Harry Kane to Bayern Munich, Spurs will be without the derby's all-time top scorer but Postecoglou said they have done well as a team so far to replace the club's "greatest player".
"There's a risk of feeling that void right from the start. That's the reality of it. It is a fairly significant figure on and off the field," he said.
"But we tried to, as a collective, focus on the road ahead, the kind of team we want to be.
"I've been really pleased with the way the lads have tackled the task of us being a real attacking threat from all areas of our game and so that people don't see a glaring gap there."
