Because the isocyanate-crosslinked copolyether binder system has poor compatibility with ammonium dinitramide (ADN), the click-chemistry propargyl-terminated ethylene oxide-tetrahydrofuran copolyether (PTPET) binder cured by multi-functional azide is introduced. In the solid propellant, the effects of spherical ADN and flaky ADN on the mechanical and combustion properties of PTPET solid propellants were investigated. The results show that the mechanical properties of the propellant prepared with the ADN-spherical were comprehensively better than those of the propellant prepared with the ADN-flaky. The epsilon(b)/epsilon(m) of the propellant with ADN-spherical was obviously lower than that of the propellant with ADN-flaky when the temperature at -40 degrees C. There was a sharp peak around -40 degrees C, followed by a broad peak, and a step rise near 40 degrees C about the DMA curves of both propellants. The burning rate measurement results showed that propellant prepared with flaky ADN had the higher burning rate at 3-17 MPa. The flame structures of both propellants showed stable combustion but the size of aluminum particles in flame zone for the propellant prepared with flaky ADN was larger.