The thermogenesis power curves of Brucellas M 5(55010) and 83 981 at 27℃ and 40℃ have been determined. From the thermogenesis power curves
a thermokinetic equation as : ln (P m /P t-1) = ln (P m /P 0-1) - k·t could be established for cell continue growth under limited condition .From this equation
the cell growth constant k were obtained. This equation is very stuitable of “S” thermogenesis power curves. This equation is very significant for the study of bacterial limited growth and their characteristics.