Microcalorimetry was used to determine the actions of some schiff base metal complexes on the Aerobacter aerogenes. Difference in their capacities to inhibit the metabolism of this bacterium, as judged from the rate constant k (in log phase), varied with the different schiff base metal complexes. The growth rate constants of the bacteria in the presence of Co(II)-NG (NG: D-glucosamine-beta-naphthol aldehyde) decreased with the increasing of its concentrations, but the relationship between k and c is not of good linearity. In the case of Fe(II)-NG the rate constants keep unvaried with the variation of its concentrations. It seems no rule in the inhibitory effect of Zn(II)-NG, Cu(II)-NG on Aerobacter aerogenes. We also found that the relation between k and P-max (the maximal thermal power) is a good linear equation, so the k can be replaced by P-max at the same experimental conditions.