Kyodo News quoted the Embassy as saying the attack occurred Monday near Zemi Valley in the Cappadocia region, a World Heritage site popular with tourists in Nevsehir province in central Turkey.
Killed in the attack was Mai Kurihara, 22, Kyodo reported. The other tourist, who was not identified, was in intensive care at a hospital.
The two, both students at Japan's Niigata University, were walking when they were attacked. Both were found lying on the ground by another tourist, the report said.
Turkish authorities said they were searching for the assailants.