The Yellow Sea is the marginal sea of the western Pacific Ocean. It borders Shandong Peninsula and Subei Plain in the west, Korea Peninsula in the east, Liaodong Peninsula in the north, Jiaozhou Bay and Haizhou Bay in the west and Korea Bay and Jianghua Bay in the east. It is a shallow sea on the continental shelf between Chinese mainland and the Korean Peninsula. The Yellow Sea is 870 kilometers long from north to south and 556 kilometers wide from east to west, with a total area of about 380,000 square kilometers.

The sea surface of the Yellow Sea suddenly opened up, because in ancient times, the Yellow River water flowed in and the rivers carried a lot of sediment, which made the sea water near the Yellow Sea yellow, so it was called the Yellow Sea. The rivers flowing into the Yellow Sea mainly include Huaihe River System, Yalu River, the border river between China and North Korea, and Datong River in North Korea. The annual variation of water temperature in the Yellow Sea is 15℃ ~ 24℃, which is less than that in the Bohai Sea. Due to the influence of continental runoff, the salinity of the Yellow Sea is low, about 32‰.

The Yellow Sea happens to be the intersection of cold current and warm current, and the aquatic products are very rich. The coastal area is flat and vast, which is suitable for drying salt. For example, the famous Luchang salt area, Shandong salt area west of Yantai and Liaodong Bay area are all important salt-producing areas in China. The Yellow Sea is also rich in tropical precious aquatic products such as sea cucumber, oyster, horseshoe snail, tuna, red fish, shark, lobster, pike, cuttlefish and squid.