The AFC asked organizers to beef up security at hotels and provide police escorts for training and matches during the tournament, which will be held in five Australian cities from Jan. 9-31.
"The confederation has expressed serious concerns over the safety and security of teams, media and fans," the AFC said in a statement.
The request came after a gunman took 17 hostages at a Sydney cafe in a 16-hour siege that ended in a police raid and barrage of gunfire early Tuesday. The gunman and two hostages were killed.
Sixteen international teams will be playing in the Asian Cup. Sydney is one of five host venues, along with Newcastle, Brisbane, Canberra and Melbourne.
AFC general secretary Dato' Alex Soosay said the confederation "is concerned about the developments in Sydney and can in no way put the safety of the players, fans and media at stake."
"Australia has successfully hosted many prestigious events in the past but the recent developments cannot be taken lightly," he said.