Settling particles were collected from three locations in the East China Sea continental margin and analyzed for 2 3 9 + 2 4 0 Pu. Two types of sediment traps were used, cylindrical traps and conical time-series traps. Surface sediment samples collected from five locations were also analyzed for 2 3 9 + 2 4 0 Pu. Data from cylindrical traps showed there was a clear tendency for total mass fluxes to increase with depth at all three stations, and there was an especially large increase near the bottom. 2 3 9 + 2 4 0 Pu concentrations in settling particles increased with depth from 1.76 mBq/g at 97-m depth to 3.00 mBq/g at 120-m depth and ranged from approximately 3 to 4 mBq/g at depths greater than 120 m. 2 3 9 + 2 4 0 Pu concentrations collected in the near-bottom traps were approximately two times higher than those in the underlying surface sediments. Like total mass fluxes there was a clear tendency for 2 3 9 + 2 4 0 Pu fluxes to increase with depth at every station, and the highest 2 3 9 + 2 4 0 Pu fluxes were observed near the bottom. 2 3 9 + 2 4 0 Pu concentrations in the time-series traps had little variation throughout the sampling period, though the total mass fluxes showed a large variation. A high variability of 2 3 9 + 2 4 0 Pu fluxes occurred in very short period of time (1/2 day). The large fluxes of 2 3 9 + 2 4 0 Pu might be attributed to episodic lateral transport of particles that flow down the continental slope with the nepheloid layer which was considered to be significant for 2 3 9 + 2 4 0 Pu transport on the continental slope in the East China Sea.