In order to study the effect of iron tannate catalyst on thermal decomposition properties of common components in solid propellants, three submicron composite microspheres,tannic acid and iron (Ta-Fe)/ hexanitrohexaazaisowurtzitane (CL-20), Ta-Fe/ cyclotrimethylenetrinitramine (RDX) and Ta-Fe/ cyclotetramethylene tetranitramine (HMX), were prepared by ultrasonic spray drying. The morphology, particle size and composition of these composites were characterized by SEM and granulometer analyser. The effect of Ta-Fe on the thermal decomposition catalytic properties and kinetic parameters of CL-20, RDX and HMX were studied by differential scanning caloriometry (DSC). Results show that Ta-Fe distributes evenly with spherical particles and good dispersibility, and the particle size distribution range is 500-1000 nm. Ta-Fe effectively promotes the thermal decomposition of CL-20, RDX and HMX, whose peak thermal decomposition temperatures decrease by 17.2，8.2 ℃ and 11.5 ℃,respectively. Especially, Ta-Fe/CL-20 has the best catalytic effect, whose activation energy is 9.6 kJ·mol^-1 lower than raw CL-20.