MgAl-HTLc compounds with different molar ratio were synthesized by the method of coprecipitation at 10℃·min-1 teating rate.Non-isothermal kinetics of thermal decomposition process were studied by TG-DTG thermal analysis method in nitrogen atmosphere.It was discovered that the thermal decomposition proceeded in three stages when n(Mg)/n(Al)=1 while in two stages when n(Mg)/n(Al)=2-6.The non-isothermal kinetic parameters were calculated by Freeman-Carrol method.