Abstract: Based on the survey data of ecological factors on April and September from 2007 to 2009, seasonal and spatial situations were investigated at 7 stations in the Haitang Bay. pH, salinity, nitrated, phosphate, chemical oxygen demand (COD) and chl-a were measured. The results showed the concentrations ranges of dissolved inorganic nitrogen (DIN) were 0.014—0.847 mg•L^-1, that of phosphate (DIP). Nitrate were 0.000 3—0.069 mg•L^-1, that of COD and chl-a values near the Tielu Harbor and Tengqiao River estuary were higher than that in the middle zones. The concentrations of phosphate near the Tielu Harbor were much higher than that in other coastal waters; the concentrations of DIN and DIP in raining seasons were higher than that in dry seasons. The data of eutrophication index (EI) calculation indicated that the zones near the Tielu harbor and Tengqiao River estuary were eutrophicated in the raining seasons, which suggested human activities have resulted in enormous nutrients entering the coastal waters in the Haitang Bay through the discharge of wastewater in industrial aquaculture and municipal sewage.