Dashan Island, also known as Danianshan and Taibujiao, is an island in the East China Sea administered as part of Qiansandao, Lianyungang Prefecture, Jiangsu Province, China.

Dashan Island has an area of 0.115 km (0.044 sq mi). It is part of the Qiansan Islands and is located 28 nmi (52 km) from Lianyungang.

It is one of the baselines of the Chinese territorial sea and the PLA erected territorial sea steles on the island in 2006.

• Suyanjiao (Suyan Rock)
• Macaiheng
• Waikejiao
• Haijiao
• Baselines of the Chinese territorial sea

• Declaration of the Government of the People's Republic of China on the baselines of the territorial sea(May15th, 1996)
• 中国东海１０座领海基点石碑建成 (in Chinese)
• 中华人民共和国政府关于中华人民共和国领海基线的声明(1996年5月15日) (in Chinese)

35°00′02″N 119°54′12″E / 35.00056°N 119.90333°E / 35.00056; 119.90333