Abstract: A chemical reaction taking place in a calorimeter is called a thermokinetic system.The recording curve of its temperature during the reaction is called a thermogram.It is very interesting to study the reaction kinetics from.its thermogram but the theory and methods of thermokinetics have not been developed into perfection yet.In this article,the thermokinetic equations of a reacting system are derived in the light of nonequilibrium thermodynamics.And the analytical expression of a thermogram can be derived from the thermokinetic equations.On this theoretical basis,a new research method in thermokinetics has been suggested