Instrumental Neutron Activation Analysis (NAA) has been applied for the determination of Ag and Sb in water column, sediment cores, and two marine organisms from Saronikos Gulf, Greece. Higher levels of Ag and Sb were found in the water column and cores from polluted areas of the Gulf as compared to those from unpolluted areas. No significant differences of Ag and Sb were found in the two marine organisms from all areas of Saronikos Gulf.