From the preface: The present book provides the distribution of terrestrial nematode from the Thar Desert of Rajasthan. The first chapter gives a detail account of methodology used to extract soil nematodes for taxonomical study. All other chapters provide the diagnostic characters of different orders, suborders, families and subfamilies with their keys according tot he systematic of nematodes species reported from Thar Desert of Rajasthan. From the taxonomical point of view, line diagram of anterior end (fig. 1) and different type of female and male reproductive organs (fig.2) of nematodes of each suborders are provided. Few habitats photograph have also been enclosed in the end of the book.