Serratia marcescens is a gram negative bacterium. It belongs to the genus Serratia and family enterobacteriaceae. This bacterium produces red coloured pigments, bio-surfactants and various types of enzymes (proteases, chitinases, lipases, nucleases, laccases) they contribuates essential role in many uses. Keeping all these benefits of Serratia marcescens in mind, here in this book we illustrated how to isolate, identify and characterize this bacterium for the research purpose and its exploitation for industrial purposes. We discussed mainly with regard to proteases. we wish this book will serve as lovely example for the reader to make them clearly easy understand about the Isolation, Identification and Molecular characterization methodologies for the Serratia marcescens and protease produced by it