The kinetics of synthesis of nanophosphor Eu0.12Y1.78La0.10O3-δ was investigated using differential thermal analysis and thermo gravimetric (DTA-TG) at different heating rates in argon gas. The results show that the precursor of nanophosphor Eu0.12Y1.78La0.10O3-δ is Y(OH)3 with hexagonal phase structure. The average apparent activation energies of the two reaction stages of the precursor were calculated using the Doyle-Ozawa and Kissinger methods they are 699.40 and 362.81 kJ·mol-1, respectively. The reaction order and frequency factor can be also determined by Kissinger method. The kinetics equations of the reaction were deduced, they are dα/dt=1.94×1046e-84120/T(1-α)1.17, dα/dt=5.89×1020e-43640/T(1-α)1.14, respectively.