Dodecyl (triphenylethynyl) silane (DTPES) was synthesized via Grignard reaction of Dodecyl trichlorosilane and phenyl acetylene in the presence of magnesium and ethyl bromide. Its chemical structure was characterized by nuclear magnetic resonance spectroscopy (1H-NMR 13C-NMR, and 29Si-NMR) and Fourier transform infrared spectroscopy (FT-IR). Its curing process was obtained by Differential Scanning Calorimetry (DSC) and the corresponding Polydodecyl(triphenylethynyl)silane resin (PDTPES) was also synthesized by thermal polymerization. The thermal decomposition behavior was analyzed by TG and DTG and the corresponding kinetic parameters and curing mechanism were discussed by six well-known kinetic methods, i.e., Kissinger, Ozawa, Friedman, Vyazonvkin-Weight, Coast-Redfern and Achar methods. Results show that the average thermal decomposition activation energy Ea was 181.51 kJ/mol and the pre-exponential factor A was 9.65?1011s-1, and the thermal decomposition kinetics equation was also proposed.