The database includes sample information and nitrogen isotope measurements of nitrate, ammonium, and amino acids in sinking particles in the Northwestern North Pacific. The sinking particles were collected in sediment traps moored at depths of 200, 500, and 4,810 m at station K2 (47°N, 160°E; water depth, ~5,200 m). The seawater was sampled with a plastic bucket for the surface and Niskin-X sampling bottles for water below the surface at stations K2 and KNOT (44°N, 155°E). The model package of a 1D nitrogen isotope model includes model source code written in Fortran 90, forcing, and initial condition at station K2.