This paper studied the distribution characteristics and pollution levels of phosphorus at the 24 sections in the DongtingLake during normal-flow period through field investigation and laboratory experiments. Besides, it analyzed the relation betweendifferent forms of phosphorus, the impacts of different forms of phosphorus on eutrophication, and releasing contents and risks ofphosphorus. The results indicate that the distribution of the total phosphorus contents during the normal-flow period ranging fromhigh to low are the Datong Lake, East Dongting Lake, West Dongting Lake and South Dongting Lake. Particulate P (PP) is thehighest content in the East Dongting Lake while dissolved P and inorganic P are the main contents in the other Lakes. Thedistribution of the total phosphorus in the sediments ranging from low to high are the Datong Lake, East Dongting Lake, WestDongting Lake and South Dongting Lake. Ca-P is the main form of P in sediments taken from the East Dongting Lake, WestDongting Lake and South Dongting Lake while Fe/Al-P in the Datong Lake. Ca-P and Fe/Al-P overwhelmingly shows negativecorrelation. The releasing contents and risks of phosphorus are high in the Datong Lake while there are some releasing contents ofphosphorus in the East Dongting Lake. Compared with other domestic lakes, the contents of TP in the sediments of the DongtingLake are not in high levels, but the contents of IP and its proportion in the TP are relatively higher. The contents of Fe/Al-P inthe sediments show negative correlation with DIP, DTP and TP respectively.