We found a water mass characterized with enormous turbidity and very low temperature in the intermediate layer of the Sea of Okhotsk in September 1999. In June 2000 and September 1999, the cold and turbid water mass was also located in bottom boundary layer on the northwestern shelf region, where sea ice had rejected large amounts of brine waters in winter. Cold brine waters settled on the bottom of shelf must have entrained sedimentary particles, including newly produced organic matter, due to strong tidal mixing, and finally flowed out into Okhotsk Sea Intermediate Water (OSIW) by a western boundary current intensified in autumn. Sediment traps moored in the deep basin recorded the outburst of particles in autumn. This mechanism is likely to export the particulate organic matter produced on the shelf efficiently to pelagic intermediate waters.