Abstract: In order to research the pyrolysis characteristics of flame retarded wood flour(WF)鄄PP composites, thermogravimetric study of flame retarded wood-plastic composites using APP and M-APP was carried out using thermogravimetric analyzer(TGA) with N2 atmosphere at different heating rates. The pyrolysis kinetic equation was found, and the activation energy of pyrolysis process was obtained by TG spectra. The results showed that the initial decomposition temperature of WF-PP composite added with M-APP decreased, and the carbon residue was improved. The maximum decomposition temperature with WF decreased from 344.8 to 334,1 c, the maximum decomposition temperature with PP was improved from 518.5 to 525.6 c, and the carbon residue was increased from 19.4% to 21.7%. Then the activation energy with added M-APP was lower than that of added APP, so flame retardant effect of M-APP is better than APP for wood flour-PP composites.