Soil is a natural body an excellent culture media for the growth and development of various types of microorganisms. Living organism which are present in the soil are grouped into two categories as Soil flora and Soil fauna mainly macrofauna and microfauna. Soil is not only an inner static material of the earth but also it is a medium which pulsating and significantly attached with our life. Soil is now believed to be a dynamic body or living system plays vital role in agriculture. Soil provides food, fodder and shelters for many birds, animal, from invertebrates such as various worms and insects up to mammals like various animals like it can be any size or shapes. The objective of learning this microorganism is to know about all these aspects, in addition to the understanding of the biological components present in the soil.