New analytical techniques using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were applied to the determination of technetium-99 (Tc-99) and neptunium-237 (Np-237) in environmental samples. The determination of Tc-99 consists of a cyclohexanone solvent extraction method to eliminate the interference isobar (Ru-99). An anion exchange with acetic acid media and a TTA-xylene solvent extraction were used for the determination of Np-237. Technetium-95m and Np-239 were used as chemical recovery tracers in these methods. The concentrations of Tc-99 and Np-237 in the typical surface soil samples in Japan ranged form 8.1×102 to 1.8×10-1 Bq/kg-dry, from 3.3×10-3 to 8.0×10-3 Bq/kg-dry, respectively.