The jets were alerted when a Chinese maritime aircraft flew about 120 km north of the Senkaku islands, which China calls the Diaoyus, a Japanese Defense Ministry spokesman said.
The Chinese Y-12 twin-turboprop later left the zone without entering Japanese airspace over the islands, he added.
This is the first time Japanese fighters have been scrambled this year to head off Chinese aircraft approaching the islands, the spokesman said.
The islands have been at the center of a dispute recently that has triggered violent anti-Japanese protests across China and caused Japanese companies to suspend operations in China.
The islands, which are also claimed by Taiwan, lie on a vital shipping route and are situated above large hydrocarbon deposits.Read the full story here.
Related: China-Japan Island Dispute