A relationship between the peak temperature and height in derivative thermogravimetry (DTG) curves was explored to seek their specific combination for addressing the uniqueness of a thermal reaction, The functional relationship between the peak temperature and height was closely related to the activation energy and reaction order, but rarely affected by the preexponential factor and heating rate. Determining peak temperature and height at a heating rate was enough to characterize a thermal reaction of first-order kinetics or known reaction order, but was insufficient to specify a reaction without knowing the shifting pattern of either peak temperature or peak height with heating rate. The peak temperature and height varied with the heating rate according to the kinetic parameters, The shifting pattern of the peak temperature with the heating rate was related to the activation energy, while that of the peak height was confined by the reaction order together with the activation energy.