$C_{60}$ is widely investigated because of its unique structure. But its applications in solid propellant seem to be relatively neglected. $C_{60}$ has more outstanding features than carbon black which is widely used as a catalyst ingredient of solid propellant. To combine the advantages of fullerene and lead salts, another good composite in propellant catalysts, we synthesized a kind of fullerene phenylalanine lead salt (FPL) and explored its thermal performances by differential thermal analysis (DTA) and thermogravimetry analysis (TGA). The results show it undergoes four exothermic processes started from 408 K. Combined TGA and X-ray diffractometer (XRD), the decomposition mechanism of FPL was derived by TG-IR and comparing IR spectra of FPL and its residues after burned to $327^{circ}C$, $376^{circ}C$ and $424^{circ}C$, respectively. Effect of FPL on the decomposition characteristic of hexogen (RDX), a type of explosive in propellant, has been investigated using DTA at different heating rate, which shows the decomposition temperatures of the explosive are all reduced by more than 20 K. The corresponding activation energy ($E_a$) is decreased by $30kJ{cdot}mol^{-1}$. So FPL has potential application as a combustion catalyst in solid propellant.