Living organism requires certain metals for their growth and metabolism and evolved an appropriate uptake mechanism for metals. However, it is particularly difficult to establish mutual relationship when soil is continuously contaminated with various heavy metals. Phosphatase enzyme significantly accelerates the release of inorganic P from organic compounds and returns it to the soil. Therefore, the study of Phosphatase enzyme that releases P from organic compounds by dephosphorylation of phosphor-ester or phosphoanhydride bond in an organic matter is an important tool in initiating biofertilizer for specific crops. The present study indicated that the availability of metal such as Zinc in its inorganic form can act as an inhibitory factor for the growth and activity of bacteria such as Pseudomonas flourescens and the biomass of P. flourescens decrease with increase ZnCl2 concentration. It can be concluded that ZnCl2 acts as an inhibitor to the growth of P. flourescens and also the presence of ZnCl2 in the growth medium decreases the phosphatase enzyme activity of the bacteria, which reveal that metals can also affect the activity of the microbes. Keywords: Biofertilizers, enzymes, microbial ecosystems, phosphatase, Pseudomonas fluorescens, ZnCl2.