The effect of lead carbonate (PbCO₃) on the combustion characteristics and thermal decomposition behavior of ammonium dinitramide (ADN) is investigated by burning rate measurement, DSC and TG techniques. Results show that the burning rate of ADN+5% PbCO₃+0.2% paraffin system is higher than that of ADN+0.2% paraffin system in the pressure range of 3-12 MPa, and PbCO₃ enables mesa combustion effect of ADN+0.2% paraffin system to disappear. TG and DSC curves of ADN and ADN+5% PbCO₃ system indicate that the initial decomposition temperature of ADN can be decreased by the addition of PbCO₃. Kinetic analysis for DSC data show that the apparent activation energy of thermal decomposition of ADN decreases when 5% PbCO₃ is added into ADN. Moreover, both combustion characteristics and surface-melting layers of ADN mixtures are considered to be correlative.