Abstract: A key task in biodiversity conservation and sustainable utilization is a powerful mean for identifying priority conservation areas （PCAs）. It is applied extensively in regions under the jurisdiction of various countries, on the high sea and on areas of international seabed. This paper discusses the processes of marine spatial classification based on biogeographic factors and the marine biodiversity classification in nearshore China. Thus, 3 level zones are divided in the nearshore China. The first level has 6 zones, i.e. the Yellow Sea， the Bohai Sea， the East China Sea， the Taiwan Strait transition zone， the South China Sea and Sansha reef zone. The second level has 16 zones， including North Yellow Sea inshore areas， South Yellow Sea inshore areas， Liaodong Bay， Bohai Bay， Laizhou Bay， the central areas of the Bohai Sea， Northern Jiangsu and the Yellow River Estuary， the Changjiang River Estuary and Hangzhou Bay， the Southeast Zhejiang coast， the Taiwan Strait transition zone， the Pearl River Estuary and Guangdong coast， Hainan coast， Beibu Bay and Guangxi coast， Xisha reef areas， Nansha reef areas and Zhongsha reef areas. The third level has 101 zones， including 14 zones in the Yellow Sea， 10 zones in the Bohai Sea， 20 zones in the East China Sea， 16 zones in the Taiwan Strait， 38 zones in the South China Sea and 3 zones in Sansha reef areas. In the end， the factors that affect the results of the spatial classification are discussed for marine diversity protection and managements．