Dredged materials in muddy port move and disperse so easily under the action of coastal hydrodynamics that the surrounding waters will be affected in various degrees if so large a quantity of sediments are dumped into the sea water. The physical, chemical and biological processes brought about by those dumped materials may affect the marine ecological equilibrium, marine resources exploration and human health. This paper presents the results of the investigation about the impact of the dredged material disposal on the coastal environment of Lianyungang. Most of capital contruction sediments are rarely polluted, which may be called as “clear sediment”. The major impact of dredged material disposal is still in physical aspect. The influence on sea environment is different for different dredged materials and all of them are not regarded as the marine pollution sources. Dredged materials in muddy port move and disperse so easily under the action of coastal hydrodynamics that the surrounding waters will be affected in various degrees if so large a quantity of sediments are dumped into the sea water. The physical, chemical and biological processes brought about by by This paper presents the results of the investigation about the impact of the dredged material disposal on the coastal environment of Lianyungang. Most of capital contruction sediments are rarely polluted, which The major impact of dredged material disposal is still in physical aspect. The influence on sea environment is different for different dredged materials and all of them are ideal as the marine pollution sources.