Polyhydroxybutyrates are biodegradable polyesters synthesized by many bacteria Biodegradable polymer plays a predominant role as a biodegradable plastic due to their hydrolysable ester bonds. In the present study fromthirty two bacterial isolates collected from clay soil rhizopher of maiz, wheat and trefoil eighteen PHB producers.PHB is highly produced from microorganisms under optimum conditions such as physical conditions (pH, temperature, incubation times),Nutritional conditions(Carbon, Nitrogen sources and C/N ratio and Biochemical conditions. Due to their biological origin it is an advantage of PHB is, they are degraded naturally and completely to carbon dioxide and water under natural environment by the enzymatic activities of microbes. The present study reports the isolation and screening of soil bacteria and subsequent PHB production under normal conditions. It was observed that clay soil was able to produce maximum yield of PHB