We are living in the ocean of microbes. These tiny microorganisms are responsible for creating atmosphere for the present day life forms. These microorganisms have immense potential to fulfill the need of the human kind. They can provide us food, fuel, fertilizer. They act as a sequesters, remediators, scavengers, and what not. The recent era is the era of biotechnology once we equipped ourself with the modern technology. It is easy to harness the potential of different microorganisms for the benefit of human kind particularly clean environment, quality food and non fossilized fuel. The judicial exploitation of microorganisms with the help of biotechnological tools not only help us to keep our environment clean, pollution free, but also help us to conserve the diversity and ultimately to protect the planet earth from any undesirable conditions. The present volume is a compendium of wide ranging current topics on microbiology, biotechnology and ecology. It is an assemblage of up to date knowledge of recent advances and development taking place in the field of microbial biotechnology and ecology. The book is a unique compilation of 50 chapters. The book "Microbial biotechnology and ecology grouped in three sections 1- Microbiology, 2-Biotechnology and 3- Ecology. The microbiology section includes about 22 articles on bacteria, cyanobacteria, VAM fungi, mushrooms. The biotechnological section includes biotechnological potential of various microorganisms and plants. In this section overall 16 articles are included. In the ecological section articles based on general ecology, bioindicators, eutropication, aquatic biodiversity, pollution etc. This section comprises of about 12 articles. The book is assemblage of scientific information contributed by eminent scientists of the country in the form of commoration volume, to give a scientific tribute to a great Mycologist and Plant Pathologist late Prof. Dr. K.M. Vyas. Who has devoted his life for the dissemination of science and scientific knowledge particularlyin the field of microbiology and biotechnology.