A method based on?cloud?point?extraction?was developed to determine?cadmium?at?the?nanogram?per?liter?level?in?sea-water?by?graphite?furnace?atomic absorption spectrometry. Diethyldithiocarbamate (DDTC) was used as?the?chelating reagent to form Cd-DDTC complex; Triton X-114 was added as?the?surfactant.?The?parameters affecting sensitivity and?extraction?efficiency (i.e., pH?of?the?solution, concentration?of?DDTC and Triton X-114, equilibration temperature, and centrifugation time) were evaluated and optimized. Under?the?optimum conditions, a preconcentration factor?of?51.6 was obtained for a 20-ml, water sample.?The?detection limit was as low as 2.0 ng L-1 and?the?analytical curve was linear?in?the?10.0-200.0 ng L-1 range with satisfactory precision (RSD < 4.7%).?The?proposed method was successfully applied to?the?trace?determination?of?cadmium?in?seawater.