A more convenient theoretical approach is developed, which can be applied to the study of solid-phase reaction by using a thermogravimetric apparatus with temperature programmer. The method proposed by the present authors to estimate the kinetic data and probable mechanism of the reaction is as follows. The temperature （T_m） corresponding to the peak of T. C. D. curve is determined experimentally for various linear heating rate (β), and then a graph of ln(T_m²/β) vs. T_m^-1 is plotted following the relation, ln(T_m²/β)+ln(41Rk₀)/E=(E/RT_m).
If a linear relationship is obtained, the activation energy and frequency factor can be calculated from the slope and intercept of the straight line. The validity of this method is confirmed by the good agreement between the value of activation energy obtained in this work and that due to previous workers for the formation reaction of barium titanate. In general, the present method may be well applied where the products of reaction are gases which eacape immediately, and particularly for step by step reaction, such as thermal desorption processes of adsorbate from adsorbent.