Jayson Castro blazed the way for the Philippines with 26 points, while Andray Blatche chipped in with 18 of his own.
Forward Samad Nikkhah Bahrami topscored for the previously unbeaten Iranian team with 21 points.
Hamed Haddadi was limited to just 10 points and 7 rebounds.
Iran will play Palestine on Tuesday while the Philippines face India.
The 2015 FIBA Asia Championship for Men is the 28th continental basketball championship in Asia. The competition is being held in Changsha from September 23 to October 3.
The winner of the tournament qualifies for the basketball tournament on the 2016 Summer Olympics, while the next three best teams will participate at the 2016 FIBA World Olympic Qualifying Tournament for Men, as stated by FIBA and the IOC in qualification quota.