Nowadays, diesel vehicles include exhaust treatment technologies, such as diesel particulate filters, to meet the emission limitations of soot. Within the particle trap, soot can be oxidized by interaction with nitrogen oxides (NOx). The extent of this interaction will depend on the specific conditions at the trap, the nitrogen oxide considered (NO2 or NO), and the nature of the soot sample. In this context, the reactivity of a standard diesel particulate matter (SRM 1650b-NIST) with NO2 has been analyzed. The tests have been performed in a laboratory quartz gas flow reactor, discontinuous for the solid, in the 723-998 K temperature range and with 100-500 ppm NO2 as an oxidant. Additionally, the soot sample has been characterized through Raman spectrometry, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Both temperature and inlet NO2 concentration are key parameters affecting the reactivity of soot with NO2. Temperatures >= 898 K are needed to achieve a complete conversion of carbon in soot and temperatures <= 973 K to limit the gas-phase conversion of NO2 into NO. Therefore, the experimental results from the tests performed in the 898-973 K temperature range have been used to determine the reaction kinetics (apparent activation energy and reaction order) of the reference diesel soot oxidation by NO2.