"The Iranian women's karate team, which comprises three athletes, will not take part in the Asian Games in Doha since the Islamic headscarves were not approved by the Asian federation," said Jabar Pour Hosseini, spokesman for the Iranian Karate Federation.
"Although we have a very good team capable of winning Asian medals, we cannot take part when our dress code is not accepted," he said.
The Islamic dress code became mandatory for mature women in Iran following the Islamic revolution in 1979.
Hosseini said that the ban on headscarves for the karate team had been imposed due to a "technical matter" related to what to do if the garment slips during a bout.
Iranian female athletes in taekwondo, another martial art in which Iran traditionally excels, will not be affected as in that sport fighters wear head guards that fully secure the headscarf in a fight.
Iranian women athletes only take part in competitions where their body and hair can be fully covered.
The Asian Games are due to start in Doha on December 1.