We investigated the effects of harvesting methods (i.e. selective cutting, clear cutting and no cutting) on the availability, spatial heterogeneity and spatial correlations of different forms of soil nitrogen in secondary forests in Northeast China over 3 years. Semivariogram analysis was applied to quantify changes of spatial heterogeneity for topsoil (0-10 cm) nitrogen. The results showed that. harvesting markedly altered the dynamics of availability, and spatial heterogeneity of soil nitrogen. Availabilities of nitrate (excluding clear cutting plot), ammonium, total nitrogen and total available nitrogen showed similar temporal patterns in selective cutting and clear cutting plots in 3 years. The temporal patterns or magnitudes in variation for parameters of semivariogram differed from harvesting and control plots. Magnitude of spatial heterogeneity (sill) for nitrogen variables, except nitrate in clear cutting plot, expressed a similar increase-then-decline pattem under two different harvesting methods. However, the dynamics of other parameters (nuggets, range and structural variance ratio) were influenced by combination of harvesting method and nitrogen forms. Spatial correlation among nitrogen variables were enhanced by harvesting, but independent of harvesting methods. Our study suggest changes of vegetation exerts a strong impacts on the availability, spatial heterogeneity and correlations of soil nitrogen variables, however, the responses of different forms of nitrogen to harvesting methods were various.