The kinetics and mechanism of depolymerization during nitroxide-mediated oxidation of native cellulose has been studied under various conditions. The physical heterogeneity of the native cellulose and its complicated hypermolecular and supramolecular structure exerts a remarkable influence on the kinetics of oxidation and depolymerization. A strong influence of external tension applied on cellulose gauze reactivity during its oxidation has been proven, which is caused by its complicated hypermolecular structure. Celluloronic acids were obtained by the application of external tension during selective oxi-contained the higher amount of carboxyl groups but they also had a lower intrinsic viscosity, i.e., the average degree of polymerization (DP). The mathematical model-socalled DP-peeling off model-has been derived to describe the kinetics of cellulose depolymerization based on experimental data obtained.