Background The use of different types of plastics in the world either synthetic or biodegradable has become a part in all sectors of the economy. Infrastructure such as agriculture, building and construction, telecommunication, consumer goods, packaging, health and medical are all high growth areas that ensure a spiralling demand for plastics. Lack of degradability, environmental pollution and closing of landfill sites has led to concern more about plastic waste disposal. Appropriate biodegradation should occur for these water-immiscible polymers since they eventually enter streams which can neither be recycled nor incinerated and also not despoiled with existing physical and chemical means of degradation. Methods In view of all these facts, area of microbial degradation for biodegradable plastics should be focussed in order to understand the role of microbes, their enzymes and the mechanism involved. Microorganisms degrading such polymers are widely distributed in environments.Intensive studies on improvement in fermentation technology are required for the economical and efficient production of enzymes from microorganisms. In this review, microbial and enzymatic degradation of biodegradable plastics and some factors that affect their production are discussed. Conclusion Here, recent patents, purification parameters and characterization of poly-D-3-hydroxybutyrate (PHB) depolymerases are also highlighted because of their huge abundance in nature and enormous applications amongst biodegradable plastics.