Abstract: Using the mierocalorimetric method the fundamental growth thermograms of Eschericher Coli, Staphylococcus acereus, Sal. Typhosa and Sal. Chaleraeuis have been determined.These perfect thermogram curves reflect the changes of bacterial growth patterns(as the lag phase of growth,exponential growth,stationary phase and the end phase of growth). In these experiments, very highly characteristic and reproducible growth patterns are observed under same condition, therefore we can use these thermograms as “finger print” to identification the bacterials. On the other hand, these thermograms curves contain ample imformation, which are very significant for the studies on microorganism metabolism, bio-thermokinetic and clinical fields.