Maintenance of complexity and heterogeneity of stand structure is one of the major concerns in forest management. The objective of this study is to evaluate how and at which scale the management impacts on stand structure of a natural fir-dominated mixed forest under the single tree selection system in Hokkaido, Japan. To this end, a series of indices of structural attributes, such as large trees, tree distribution, stratum structure, deadwoods, and understory vegetation, were analyzed at different spatial resolutions to compare complexity and heterogeneity of a managed stand and an unmanaged stand. The structural indices associated with overstory trees were not remarkably different between the managed and the unmanaged stand. On the other hand, the amount, the composition, and the spatial distribution of deadwoods were altered significantly by the management. Furthermore, several differences of the understory vegetation between the stands suggested that the management has some impacts on regeneration pattern. These results indicate that the effects of selection cutting on stand structure differed according to which attribute and which scale to be focused on. Multiple scales in accordance with each structural attribute should be taken in to account to improve the management.