The 35-year-old lifted two Premier League titles and three FA Cups during nine seasons in North London between 1998 and 2007.
However, since he left the club in a £3m move to West Ham United, the Gunners have failed to claim a single piece of major silverware.
"I am a fan like everyone else and I want us to win trophies," Ljungberg told The Mirror. "That hasn't happened for seven years and maybe Arsene Wenger doesn't get the funding.
"All I know is that when I was at Arsenal, every summer he was able to bring in a big signing, a proven winner. Thierry Henry came as a World Cup winner, and then Robert Pires arrived. He was also a World Cup winner and, like Thierry, a Euro winner as well.
"We were able to get Sol Campbell, who was one of the best central defenders in the world at the time. They were people who knew what it takes to win. It happened like that every year.
"We had a really squad, but Arsene was able to make it better, make it stronger. That doesn't seem to happen now. It is unfair to just blame Arsene because he is a fantastic manager.
"I just hope that he can be given the money to fund the transfers he wants. I wouldn't know if the board is giving Arsene the money to do that."
Ljungberg recently revealed that he is planning to join the coaching staff at the Emirates Stadium ahead of next season.