The capital club have spent big since being taken over by Qatar Investment Authority two years ago, which helped them capture the league title last season.
With Laurent Blanc's men losing just once in their opening 17 games this term, many have posited that teams in the French league are not strong enough to thwart Les Parisiens.
However, the 32-year-old Swede has said that every week presents a difficult challenge, as teams double their efforts in order to score a morale-boosting victory.
"We must stop saying that the championship of France is too easy for Paris Saint-Germain," Ibrahimovic told the club's official website. "Each team is complicated to deal with and there is always a lot of commitment.
"Physically, the Ligue 1 is impressive. With each game, all of the pressure is on us, while our opponents play the game of their season.
"Upsetting PSG, the defending champions, boosts their motivation. They do not play to 100, but 200%. So, nothing is ever simple, even if we do everything to make it become so."
PSG are top of the league.