The family Tetranychidae or spider mites include the most injurious plant-feeding mites. Some infest a wide range of host plant whereas some others are highly specific. The family includes about 12,000 species of phytophagous mites which can rapidly disperse to exploit new feeding sites, damage agricultural and horticultural crops causing severe economic losses. Precise identification up to species level is difficult since all species look similar. Hence molecular methods are increasingly applied in tetranychid mite taxonomy to establish species identity and DNA barcoding is the best option for this purpose. DNA barcoding is a novel system designed to provide rapid, accurate, and automatable species identification using short, standardized gene regions as internal species tags. This book throws light on the generation of DNA barcodes for different species of spider mites in vegetable crops and analyse the intra and inter species genetic relationship. This book is useful for the Taxonomists, Geneticists, Pathologists, ecologists, conservation biologists and molecular biologists.