The bomb went off on Saturday at the foot of a statue in downtown Kusadasi, a popular tourist resort south of the port city of Izmir.
No one claimed responsibility for the attack, but Kurdish rebels, radical Islamist groups and leftist militants are all active in Turkey.
Police went to the scene following a tip that a bomb was placed near a statue of Mustafa Kemal Ataturk, the founder of modern Turkey. It exploded as police tried to defuse it, Mustafa Malay, the governor of Aydin province, told private NTV television.
Five police officers were taken to hospitals, Malay said. One, identified as Yasar Aykac, whose arm was ripped off and who suffered injuries to internal organs, later died at a hospital in Izmir, an emergency room official said.
The bomb went off at about noon as the officers were cordoning off the scene. No civilians were injured, Malay said.
Television footage showed officers lying in pools of blood on the asphalt road as citizens and medical teams struggled to carry them to an ambulance.
Abdullah Ocalan was captured in
1999 and put on trial
Malay said there was no clear information as to who was behind the attack. Kusadasi was the scene of a 1993 bomb attack by Kurdish rebels, which wounded 18 people, including six foreigners.
Rebels of the Kurdistan Workers' Party, or PKK, have battled government forces in a conflict that has killed more than 37,000 people since 1984 in southeastern Turkey.
Fighting in the region tapered off after a truce in 1999, which followed the capture of rebel leader Abdullah Ocalan. But there has been a surge in violence since 1 June 2004, when the rebels declared an end to the ceasefire, saying Turkey had not responded in kind.