Geumgwan Gaya, also known as Bongaya (본가야, 本伽倻) (meaning the "original Gaya") was a major chiefdom of the Gaya confederacy. It is believed to have been located in modern-day Gimhae, South Gyeongsang, near the mouth of the Nakdong River. Aided by its strategic location, this kingdom played a dominant role in the regional affairs from the Byeonhan period forward.
Royal tombs attributed to Geumgwan Gaya were unearthed in Daeseong-dong, Gimhae in the early 1990s. Interestingly, this tomb complex appears to have been used since Byeonhan times. However, a sharp break in burial styles is found around the later 3rd century. Burial forms associated with North Asian nomadic peoples, such as the burial of horses with the dead, suddenly replace earlier forms in the tombs of the elite (Cheol 2000). In addition, earlier burials were systematically destroyed. Partially on this basis, Cheol (2000) argues that the rulership of Geumgwan Gaya was taken over by invaders from Buyeo after the decline of the Chinese commanderies.