The burning rate of ammonium dinitramide (ADN) has been studied as a function of pressure and different additives, the temperatures in the combustion front, and the composition of combustion products. Some kinetic characteristics of decomposition have been also obtained. A combustion model has been used that accounts for decomposition and evaporation, and calculated parameters of combustion are compared with experimental data. The mechanism of ADN combustion is similar to that of many other onium salts. Its peculiarities are conditioned by a rather high decomposition rate in the liquid state, low reactivity of decomposition products, and formation of ammonium nitrate as an intermediate product at low pressures.