The Kofun period (古墳時代, Kofun jidai) is an era in the history of Japan from about 300 to 538 AD (the date of the introduction of Buddhism), following the Yayoi period. The Kofun and the subsequent Asuka periods are sometimes collectively called the Yamato period.

In the late Kofun Period, burial mounds became smaller and more widely used by people of lower status, with groups of 15-meter mounds forming cemeteries. The earliest Kofun were found in central Honshu around the modern-day prefectures of Kyoto, Nara, and Osaka.

The Kofun period is named after the tomb mounds that were built for members of the ruling class during this time. The practice of building sepulchral mounds and burying treasures with the dead was transmitted to Japan from the Asian continent about the third century A.D.

The Kofun period is named after kofun — gigantic earthen burial mounds (tumuli). First were built for important people and often surrounded by a moat, they came in different shapes — round-, square- and keyhole-shaped — and were similar to graves found in China and Korea.