The thermal degradation of wool treated with flame-retardant reagents synthesized in our laboratory, namely, (NH4)(3)H2PO4 [Al(H2PO4)(5)], (NH4)(3)Cl[Ca(H2PO4)(4)], (NH4)(3)Cl [Mg (H2PO4)(4)], (NH4)(3)H2PO4 [Zn(H2PO4)(4)], K(NH4)(2)Cl[Zn(H2PO4)(4)], Na3Cl[Zn(H2PO4)(4)] and H3PO4[Zn(H2PO4)(2)] was studied by thermal analysis, infrared spectroscopy and by measurement of the limiting oxygen index (LOI). The kinetic parameters were obtained using the equations of Brodio and Kissinger. The activation energies were calculated for the decomposition of untreated wool and wool treated with flame-retardant reagents. Experimental data showed that for the wool treated with flame-retardant reagents there were increases in char yield and LOI, and decreases in the activation energy and the temperature of decomposition.