Bolshoi Ussuriysky Island (Russian: о́стров Большо́й Уссури́йский), or Heixiazi Island (simplified Chinese: 黑瞎子岛; traditional Chinese: 黑瞎子島; pinyin: Hēixiāzi Dǎo), is a sedimentary island at the confluence of the Ussuri and Amur rivers. It is divided between the People's Republic of China (PRC) and Russia. It has an area of about 327 to 350 km² and is bounded closely by Yinlong Island (Tarabarov Island), and over ninety islets (in Chinese, Heixiazi may refer only to the large island or to the island group collectively).